Bug 103751

Summary: M-Audio Fast Track Ultra usb audio device will not operate full-duplex
Product: Drivers Reporter: grozzy
Component: Sound(ALSA)Assignee: Jaroslav Kysela (perex)
Status: NEW ---    
Severity: normal CC: alexander, francois.jacques, matare, superquad.vortex2
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 4.1.5-1-ARCH Subsystem:
Regression: No Bisected commit-id:

Description grozzy 2015-08-30 18:15:46 UTC
[1.] One line summary of the problem:  M-Audio Fast Track Ultra usb audio device will not operate full-duplex.
   
[2.] Full description of the problem/report:  I originally noticed this problem while attempting to record audio in Ardour 4.2.
Further testing with the alsa utilities points to a driver problem.  Playback works as expected.  Recording works as expected.
Playback and recording simultaneously does not work as expected, as described below.  To test simultaneous playback and record:

'speaker-test -c2 -Dplughw:Ultra'

'arecord -fdat -Dplughw:Ultra /dev/null'

'dmesg'

When playback is active, starting recording will cause playback audio to drop with these errors:

'arecord -fdat -Dplughw:Ultra /dev/null'
Recording WAVE '/dev/null' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo
arecord: set_params:1297: Unable to install hw params:
ACCESS:  RW_INTERLEAVED
FORMAT:  S16_LE
SUBFORMAT:  STD
SAMPLE_BITS: 16
FRAME_BITS: 32
CHANNELS: 2
RATE: 48000
PERIOD_TIME: 125000
PERIOD_SIZE: 6000
PERIOD_BYTES: 24000
PERIODS: 4
BUFFER_TIME: 500000
BUFFER_SIZE: 24000
BUFFER_BYTES: 96000
TICK_TIME: 0

'dmesg'
usb 4-1.1: Unable to change format on ep #81: already in use

When recording is active, starting playback will cause playback audio to drop with these errors:

'speaker-test -c2 -Dplughw:Ultra'
speaker-test 1.0.29

Playback device is plughw:Ultra
Stream parameters are 48000Hz, S16_LE, 2 channels
Using 16 octaves of pink noise
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 12 to 43690
Period size range from 6 to 21845
Using max buffer size 43688
Periods = 4
Unable to set hw params for playback: Device or resource busy
Setting of hwparams failed: Device or resource busy

'dmesg'
usb 4-1.1: Unable to change format on ep #81: already in use
 
[3.] Keywords (i.e., modules, networking, kernel):  m-audio fast track ultra, usb audio, endpoint

[4.] Kernel version (from /proc/version):  Linux version 4.1.5-1-ARCH (builduser@tobias) (gcc version 5.2.0 (GCC) ) #1 SMP PREEMPT Tue Aug 11 15:41:14 CEST 2015

[5.] Output of Oops.. message (if applicable) with symbolic information 
     resolved (see Documentation/oops-tracing.txt)

[6.] A small shell script or example program which triggers the
     problem (if possible):  See [2] Full description.

[7.] Environment:

[7.1.] Software (add the output of the ver_linux script here)

[7.2.] Processor information (from /proc/cpuinfo):
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 825.601
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 0
cpu cores	: 4
apicid		: 0
initial apicid	: 0
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 1
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 819.156
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 0
cpu cores	: 4
apicid		: 1
initial apicid	: 1
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 2
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 885.757
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 1
cpu cores	: 4
apicid		: 2
initial apicid	: 2
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 3
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 828.781
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 1
cpu cores	: 4
apicid		: 3
initial apicid	: 3
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 4
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 799.992
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 2
cpu cores	: 4
apicid		: 4
initial apicid	: 4
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 5
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 799.992
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 2
cpu cores	: 4
apicid		: 5
initial apicid	: 5
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 6
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 961.125
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 3
cpu cores	: 4
apicid		: 6
initial apicid	: 6
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 7
vendor_id	: GenuineIntel
cpu family	: 6
model		: 42
model name	: Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz
stepping	: 7
microcode	: 0x17
cpu MHz		: 898.992
cache size	: 6144 KB
physical id	: 0
siblings	: 8
core id		: 3
cpu cores	: 4
apicid		: 7
initial apicid	: 7
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveopt
bugs		:
bogomips	: 4391.16
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:
  

[7.3.] Module information (from /proc/modules):
snd_usb_audio 151552 0 - Live 0xffffffffa0699000
snd_usbmidi_lib 28672 1 snd_usb_audio, Live 0xffffffffa0450000
snd_rawmidi 28672 1 snd_usbmidi_lib, Live 0xffffffffa0529000
snd_seq_device 16384 1 snd_rawmidi, Live 0xffffffffa03a3000
nls_utf8 16384 1 - Live 0xffffffffa0348000
isofs 40960 1 - Live 0xffffffffa051e000
fuse 90112 3 - Live 0xffffffffa04fb000
joydev 20480 0 - Live 0xffffffffa039d000
mousedev 20480 0 - Live 0xffffffffa030c000
arc4 16384 2 - Live 0xffffffffa0375000
intel_rapl 20480 0 - Live 0xffffffffa037a000
iosf_mbi 16384 1 intel_rapl, Live 0xffffffffa05c9000
x86_pkg_temp_thermal 16384 0 - Live 0xffffffffa0537000
intel_powerclamp 16384 0 - Live 0xffffffffa0370000
snd_hda_codec_hdmi 53248 1 - Live 0xffffffffa04ed000
coretemp 16384 0 - Live 0xffffffffa0313000
iwldvm 188416 0 - Live 0xffffffffa0a09000
mac80211 667648 1 iwldvm, Live 0xffffffffa08c9000
snd_hda_codec_realtek 77824 1 - Live 0xffffffffa043c000
iTCO_wdt 16384 0 - Live 0xffffffffa02c3000
snd_hda_codec_generic 69632 1 snd_hda_codec_realtek, Live 0xffffffffa042a000
iTCO_vendor_support 16384 1 iTCO_wdt, Live 0xffffffffa027f000
i915 1044480 3 - Live 0xffffffffa0706000
kvm 442368 0 - Live 0xffffffffa062c000
snd_hda_intel 28672 3 - Live 0xffffffffa0516000
uvcvideo 90112 0 - Live 0xffffffffa05ce000
snd_hda_controller 28672 1 snd_hda_intel, Live 0xffffffffa05c1000
crct10dif_pclmul 16384 0 - Live 0xffffffffa02a8000
crc32_pclmul 16384 0 - Live 0xffffffffa029d000
iwlwifi 176128 1 iwldvm, Live 0xffffffffa05e7000
crc32c_intel 24576 0 - Live 0xffffffffa05b1000
snd_hda_codec 98304 5 snd_hda_codec_hdmi,snd_hda_codec_realtek,snd_hda_codec_generic,snd_hda_intel,snd_hda_controller, Live 0xffffffffa0592000
ghash_clmulni_intel 16384 0 - Live 0xffffffffa0462000
videobuf2_vmalloc 16384 1 uvcvideo, Live 0xffffffffa046b000
aesni_intel 172032 0 - Live 0xffffffffa0567000
videobuf2_memops 16384 1 videobuf2_vmalloc, Live 0xffffffffa03b7000
videobuf2_core 40960 1 uvcvideo, Live 0xffffffffa03d8000
drm_kms_helper 106496 1 i915, Live 0xffffffffa053e000
snd_hda_core 28672 5 snd_hda_codec_hdmi,snd_hda_codec_realtek,snd_hda_codec_generic,snd_hda_controller,snd_hda_codec, Live 0xffffffffa03c2000
v4l2_common 16384 1 videobuf2_core, Live 0xffffffffa045d000
aes_x86_64 20480 1 aesni_intel, Live 0xffffffffa03cf000
lrw 16384 1 aesni_intel, Live 0xffffffffa0458000
cfg80211 483328 3 iwldvm,mac80211,iwlwifi, Live 0xffffffffa0471000
snd_hwdep 16384 2 snd_usb_audio,snd_hda_codec, Live 0xffffffffa03a9000
drm 286720 5 i915,drm_kms_helper, Live 0xffffffffa03e3000
gf128mul 16384 1 lrw, Live 0xffffffffa03bd000
snd_pcm 90112 5 snd_usb_audio,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_controller,snd_hda_codec, Live 0xffffffffa0386000
jmb38x_ms 20480 0 - Live 0xffffffffa0380000
videodev 139264 3 uvcvideo,videobuf2_core,v4l2_common, Live 0xffffffffa034d000
snd_timer 28672 1 snd_pcm, Live 0xffffffffa0340000
memstick 16384 1 jmb38x_ms, Live 0xffffffffa0298000
snd 69632 18 snd_usb_audio,snd_usbmidi_lib,snd_rawmidi,snd_seq_device,snd_hda_codec_hdmi,snd_hda_codec_realtek,snd_hda_codec_generic,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_timer, Live 0xffffffffa02fa000
intel_gtt 20480 1 i915, Live 0xffffffffa02f4000
i2c_i801 20480 0 - Live 0xffffffffa02ee000
glue_helper 16384 1 aesni_intel, Live 0xffffffffa0293000
mei_me 24576 0 - Live 0xffffffffa02e7000
media 20480 2 uvcvideo,videodev, Live 0xffffffffa02a2000
ablk_helper 16384 1 aesni_intel, Live 0xffffffffa0153000
evdev 24576 14 - Live 0xffffffffa024b000
i2c_algo_bit 16384 1 i915, Live 0xffffffffa0158000
mei 77824 1 mei_me, Live 0xffffffffa032c000
mac_hid 16384 0 - Live 0xffffffffa025a000
soundcore 16384 1 snd, Live 0xffffffffa025f000
i2c_core 49152 7 i915,drm_kms_helper,v4l2_common,drm,videodev,i2c_i801,i2c_algo_bit, Live 0xffffffffa031f000
lpc_ich 24576 0 - Live 0xffffffffa0318000
cryptd 20480 3 ghash_clmulni_intel,aesni_intel,ablk_helper, Live 0xffffffffa026a000
psmouse 122880 0 - Live 0xffffffffa02c8000
shpchp 36864 0 - Live 0xffffffffa0275000
serio_raw 16384 0 - Live 0xffffffffa0252000
ideapad_laptop 24576 0 - Live 0xffffffffa01e5000
pcspkr 16384 0 - Live 0xffffffffa0246000
sparse_keymap 16384 1 ideapad_laptop, Live 0xffffffffa0144000
rfkill 24576 4 cfg80211,ideapad_laptop, Live 0xffffffffa0285000
fan 16384 0 - Live 0xffffffffa0270000
wmi 20480 0 - Live 0xffffffffa0264000
thermal 20480 0 - Live 0xffffffffa02bd000
battery 20480 0 - Live 0xffffffffa02b3000
ac 16384 0 - Live 0xffffffffa02ae000
video 24576 1 i915, Live 0xffffffffa028c000
processor 28672 0 - Live 0xffffffffa01dd000
button 16384 1 i915, Live 0xffffffffa0135000
sch_fq_codel 20480 5 - Live 0xffffffffa00a9000
ip_tables 28672 0 - Live 0xffffffffa00b6000
x_tables 28672 1 ip_tables, Live 0xffffffffa0044000
ext4 516096 1 - Live 0xffffffffa015e000
crc16 16384 1 ext4, Live 0xffffffffa002b000
mbcache 20480 1 ext4, Live 0xffffffffa001a000
jbd2 90112 1 ext4, Live 0xffffffffa011e000
sr_mod 24576 1 - Live 0xffffffffa00af000
cdrom 53248 1 sr_mod, Live 0xffffffffa007a000
sd_mod 36864 2 - Live 0xffffffffa0010000
ahci 36864 2 - Live 0xffffffffa0149000
libahci 28672 1 ahci, Live 0xffffffffa013c000
xhci_pci 16384 0 - Live 0xffffffffa0032000
ehci_pci 16384 0 - Live 0xffffffffa003f000
libata 204800 2 ahci,libahci, Live 0xffffffffa0213000
xhci_hcd 155648 1 xhci_pci, Live 0xffffffffa01ec000
ehci_hcd 73728 1 ehci_pci, Live 0xffffffffa004c000
atkbd 24576 0 - Live 0xffffffffa0038000
sdhci_pci 24576 0 - Live 0xffffffffa0020000
libps2 16384 2 psmouse,atkbd, Live 0xffffffffa00be000
sdhci 40960 1 sdhci_pci, Live 0xffffffffa006f000
led_class 16384 2 iwldvm,sdhci, Live 0xffffffffa006a000
scsi_mod 151552 3 sr_mod,sd_mod,libata, Live 0xffffffffa00f8000
usbcore 200704 7 snd_usb_audio,snd_usbmidi_lib,uvcvideo,xhci_pci,ehci_pci,xhci_hcd,ehci_hcd, Live 0xffffffffa00c6000
mmc_core 114688 2 sdhci_pci,sdhci, Live 0xffffffffa008c000
usb_common 16384 1 usbcore, Live 0xffffffffa0062000
i8042 20480 2 ideapad_laptop,libps2, Live 0xffffffffa000a000
serio 20480 6 psmouse,serio_raw,atkbd,i8042, Live 0xffffffffa0000000

[7.4.] Loaded driver and hardware information (/proc/ioports, /proc/iomem):

/pro/ioports
0000-0cf7 : PCI Bus 0000:00
  0000-001f : dma1
  0020-0021 : pic1
  0040-0043 : timer0
  0050-0053 : timer1
  0060-0060 : keyboard
  0062-0062 : PNP0C09:00
    0062-0062 : EC data
  0064-0064 : keyboard
  0066-0066 : PNP0C09:00
    0066-0066 : EC cmd
  0070-0077 : rtc0
  0080-008f : dma page reg
  00a0-00a1 : pic2
  00c0-00df : dma2
  00f0-00ff : fpu
    00f0-00f0 : PNP0C04:00
  03c0-03df : vesafb
  0400-0403 : ACPI PM1a_EVT_BLK
  0404-0405 : ACPI PM1a_CNT_BLK
  0408-040b : ACPI PM_TMR
  0410-0415 : ACPI CPU throttle
  0420-042f : ACPI GPE0_BLK
  0430-0433 : iTCO_wdt
    0430-0433 : iTCO_wdt
  0450-0450 : ACPI PM2_CNT_BLK
  0454-0457 : pnp 00:02
  0458-047f : pnp 00:00
    0460-047f : iTCO_wdt
      0460-047f : iTCO_wdt
  0500-057f : pnp 00:00
  0680-069f : pnp 00:00
0cf8-0cff : PCI conf1
0d00-ffff : PCI Bus 0000:00
  1000-100f : pnp 00:00
  1010-1013 : pnp 00:00
  164e-164f : pnp 00:00
  2000-2fff : PCI Bus 0000:01
  3000-303f : 0000:00:02.0
  3040-305f : 0000:00:1f.3
  3060-307f : 0000:00:1f.2
    3060-307f : ahci
  3080-3087 : 0000:00:1f.2
    3080-3087 : ahci
  3088-308f : 0000:00:1f.2
    3088-308f : ahci
  3098-309b : 0000:00:1f.2
    3098-309b : ahci
  309c-309f : 0000:00:1f.2
    309c-309f : ahci
  ffff-ffff : pnp 00:00

/proc/iomem
00000000-00000fff : reserved
00001000-0009d7ff : System RAM
0009d800-0009ffff : reserved
000a0000-000bffff : PCI Bus 0000:00
000c0000-000cf1ff : Video ROM
000e0000-000fffff : reserved
  000f0000-000fffff : System ROM
00100000-1fffffff : System RAM
  01000000-01590f1e : Kernel code
  01590f1f-018df5bf : Kernel data
  01a0e000-01b2dfff : Kernel bss
20000000-201fffff : reserved
  20000000-201fffff : pnp 00:06
20200000-3fffffff : System RAM
40000000-401fffff : reserved
  40000000-401fffff : pnp 00:06
40200000-bce3efff : System RAM
bce3f000-bcebefff : reserved
bcebf000-bcfbefff : ACPI Non-volatile Storage
bcfbf000-bcffefff : ACPI Tables
bcfff000-bcffffff : System RAM
bd000000-bf9fffff : reserved
  bda00000-bf9fffff : Graphics Stolen Memory
bfa00000-feafffff : PCI Bus 0000:00
  bfa00000-bfa00fff : pnp 00:05
  c0000000-cfffffff : 0000:00:02.0
  d0000000-d03fffff : 0000:00:02.0
  d0400000-d13fffff : PCI Bus 0000:01
  d1400000-d14fffff : PCI Bus 0000:0a
    d1400000-d14000ff : 0000:0a:00.4
    d1401000-d14010ff : 0000:0a:00.3
      d1401000-d14010ff : jmb38x_ms
    d1402000-d14020ff : 0000:0a:00.2
    d1403000-d14030ff : 0000:0a:00.0
      d1403000-d14030ff : mmc0
  d1500000-d15fffff : PCI Bus 0000:09
    d1500000-d1501fff : 0000:09:00.0
      d1500000-d1501fff : xhci-hcd
  d1600000-d16fffff : PCI Bus 0000:08
    d1600000-d1601fff : 0000:08:00.0
      d1600000-d1601fff : iwlwifi
  d1700000-d26fffff : PCI Bus 0000:01
  d2700000-d2703fff : 0000:00:1b.0
    d2700000-d2703fff : ICH HD audio
  d2704000-d270400f : 0000:00:16.0
    d2704000-d270400f : mei_me
  d2706000-d27060ff : 0000:00:1f.3
  d2708000-d27087ff : 0000:00:1f.2
    d2708000-d27087ff : ahci
  d2709000-d27093ff : 0000:00:1d.0
    d2709000-d27093ff : ehci_hcd
  d270a000-d270a3ff : 0000:00:1a.0
    d270a000-d270a3ff : ehci_hcd
  f8000000-fbffffff : PCI MMCONFIG 0000 [bus 00-3f]
    f8000000-fbffffff : reserved
      f8000000-fbffffff : pnp 00:05
feb00000-feb03fff : reserved
fec00000-fec00fff : reserved
  fec00000-fec003ff : IOAPIC 0
fed00000-fed003ff : HPET 0
  fed00000-fed003ff : PNP0103:00
fed10000-fed19fff : reserved
  fed10000-fed17fff : pnp 00:05
  fed18000-fed18fff : pnp 00:05
  fed19000-fed19fff : pnp 00:05
fed1c000-fed1ffff : reserved
  fed1c000-fed1ffff : pnp 00:05
    fed1f410-fed1f414 : iTCO_wdt
      fed1f410-fed1f414 : iTCO_wdt
fed20000-fed3ffff : pnp 00:05
fed90000-fed93fff : pnp 00:05
fee00000-fee00fff : Local APIC
  fee00000-fee00fff : reserved
ff000000-ffffffff : INT0800:00
  ffd80000-ffffffff : reserved
100000000-23fdfffff : System RAM
23fe00000-23fffffff : RAM buffer

[7.5.] PCI information ('lspci -vvv' as root)
00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09)
	Subsystem: Lenovo Device 3975
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ >SERR- <PERR- INTx-
	Latency: 0
	Capabilities: <access denied>

00:01.0 PCI bridge: Intel Corporation Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port (rev 09) (prog-if 00 [Normal decode])
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 24
	Bus: primary=00, secondary=01, subordinate=06, sec-latency=0
	I/O behind bridge: 00002000-00002fff
	Memory behind bridge: d1700000-d26fffff
	Prefetchable memory behind bridge: 00000000d0400000-00000000d13fffff
	Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
	BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
		PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
	Capabilities: <access denied>
	Kernel driver in use: pcieport
	Kernel modules: shpchp

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller])
	Subsystem: Lenovo Device 3981
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Interrupt: pin A routed to IRQ 37
	Region 0: Memory at d0000000 (64-bit, non-prefetchable) [size=4M]
	Region 2: Memory at c0000000 (64-bit, prefetchable) [size=256M]
	Region 4: I/O ports at 3000 [size=64]
	Expansion ROM at <unassigned> [disabled]
	Capabilities: <access denied>
	Kernel driver in use: i915
	Kernel modules: i915

00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04)
	Subsystem: Lenovo Device 3975
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Interrupt: pin A routed to IRQ 34
	Region 0: Memory at d2704000 (64-bit, non-prefetchable) [size=16]
	Capabilities: <access denied>
	Kernel driver in use: mei_me
	Kernel modules: mei_me

00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 05) (prog-if 20 [EHCI])
	Subsystem: Lenovo Device 3975
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Interrupt: pin A routed to IRQ 16
	Region 0: Memory at d270a000 (32-bit, non-prefetchable) [size=1K]
	Capabilities: <access denied>
	Kernel driver in use: ehci-pci
	Kernel modules: ehci_pci

00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05)
	Subsystem: Lenovo Device 3975
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 36
	Region 0: Memory at d2700000 (64-bit, non-prefetchable) [size=16K]
	Capabilities: <access denied>
	Kernel driver in use: snd_hda_intel
	Kernel modules: snd_hda_intel

00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b5) (prog-if 00 [Normal decode])
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 17
	Bus: primary=00, secondary=07, subordinate=07, sec-latency=0
	I/O behind bridge: 0000f000-00000fff
	Memory behind bridge: fff00000-000fffff
	Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
	Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ <SERR- <PERR-
	BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
		PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
	Capabilities: <access denied>
	Kernel driver in use: pcieport
	Kernel modules: shpchp

00:1c.1 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 2 (rev b5) (prog-if 00 [Normal decode])
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin B routed to IRQ 16
	Bus: primary=00, secondary=08, subordinate=08, sec-latency=0
	I/O behind bridge: 0000f000-00000fff
	Memory behind bridge: d1600000-d16fffff
	Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
	Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ <SERR- <PERR-
	BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
		PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
	Capabilities: <access denied>
	Kernel driver in use: pcieport
	Kernel modules: shpchp

00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b5) (prog-if 00 [Normal decode])
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin D routed to IRQ 19
	Bus: primary=00, secondary=09, subordinate=09, sec-latency=0
	I/O behind bridge: 0000f000-00000fff
	Memory behind bridge: d1500000-d15fffff
	Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
	Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ <SERR- <PERR-
	BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
		PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
	Capabilities: <access denied>
	Kernel driver in use: pcieport
	Kernel modules: shpchp

00:1c.4 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 5 (rev b5) (prog-if 00 [Normal decode])
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 17
	Bus: primary=00, secondary=0a, subordinate=0a, sec-latency=0
	I/O behind bridge: 0000f000-00000fff
	Memory behind bridge: d1400000-d14fffff
	Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
	Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ <SERR- <PERR-
	BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
		PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
	Capabilities: <access denied>
	Kernel driver in use: pcieport
	Kernel modules: shpchp

00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 05) (prog-if 20 [EHCI])
	Subsystem: Lenovo Device 3975
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Interrupt: pin A routed to IRQ 23
	Region 0: Memory at d2709000 (32-bit, non-prefetchable) [size=1K]
	Capabilities: <access denied>
	Kernel driver in use: ehci-pci
	Kernel modules: ehci_pci

00:1f.0 ISA bridge: Intel Corporation HM65 Express Chipset Family LPC Controller (rev 05)
	Subsystem: Lenovo Device 3975
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Capabilities: <access denied>
	Kernel driver in use: lpc_ich
	Kernel modules: lpc_ich

00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller (rev 05) (prog-if 01 [AHCI 1.0])
	Subsystem: Lenovo Device 3975
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Interrupt: pin B routed to IRQ 33
	Region 0: I/O ports at 3088 [size=8]
	Region 1: I/O ports at 309c [size=4]
	Region 2: I/O ports at 3080 [size=8]
	Region 3: I/O ports at 3098 [size=4]
	Region 4: I/O ports at 3060 [size=32]
	Region 5: Memory at d2708000 (32-bit, non-prefetchable) [size=2K]
	Capabilities: <access denied>
	Kernel driver in use: ahci
	Kernel modules: ahci

00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05)
	Subsystem: Lenovo Device 3975
	Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Interrupt: pin C routed to IRQ 19
	Region 0: Memory at d2706000 (64-bit, non-prefetchable) [size=256]
	Region 4: I/O ports at 3040 [size=32]
	Kernel modules: i2c_i801

08:00.0 Network controller: Intel Corporation Centrino Wireless-N 1000 [Condor Peak]
	Subsystem: Intel Corporation Centrino Wireless-N 1000 BGN
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 35
	Region 0: Memory at d1600000 (64-bit, non-prefetchable) [size=8K]
	Capabilities: <access denied>
	Kernel driver in use: iwlwifi
	Kernel modules: iwlwifi

09:00.0 USB controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04) (prog-if 30 [XHCI])
	Subsystem: Lenovo Device 3975
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 19
	Region 0: Memory at d1500000 (64-bit, non-prefetchable) [size=8K]
	Capabilities: <access denied>
	Kernel driver in use: xhci_hcd
	Kernel modules: xhci_pci

0a:00.0 System peripheral: JMicron Technology Corp. SD/MMC Host Controller (rev 30)
	Subsystem: Lenovo Device 3976
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 16
	Region 0: Memory at d1403000 (32-bit, non-prefetchable) [size=256]
	Capabilities: <access denied>
	Kernel driver in use: sdhci-pci
	Kernel modules: sdhci_pci

0a:00.2 SD Host controller: JMicron Technology Corp. Standard SD Host Controller (rev 30) (prog-if 01)
	Subsystem: Lenovo Device 3976
	Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Interrupt: pin A routed to IRQ 16
	Region 0: Memory at d1402000 (32-bit, non-prefetchable) [size=256]
	Capabilities: <access denied>
	Kernel modules: sdhci_pci

0a:00.3 System peripheral: JMicron Technology Corp. MS Host Controller (rev 30)
	Subsystem: Lenovo Device 3976
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 16
	Region 0: Memory at d1401000 (32-bit, non-prefetchable) [size=256]
	Capabilities: <access denied>
	Kernel driver in use: jmb38x_ms
	Kernel modules: jmb38x_ms

0a:00.4 System peripheral: JMicron Technology Corp. xD Host Controller (rev 30)
	Subsystem: Lenovo Device 3976
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 7
	Region 0: Memory at d1400000 (32-bit, non-prefetchable) [size=256]
	Capabilities: <access denied>

[7.6.] SCSI information (from /proc/scsi/scsi)
Host: scsi0 Channel: 00 Id: 00 Lun: 00
  Vendor: ATA      Model: SAMSUNG MZMPA064 Rev: 8L1Q
  Type:   Direct-Access                    ANSI  SCSI revision: 05
Host: scsi1 Channel: 00 Id: 00 Lun: 00
  Vendor: ATA      Model: WDC WD7500BPVT-2 Rev: 1A03
  Type:   Direct-Access                    ANSI  SCSI revision: 05
Host: scsi2 Channel: 00 Id: 00 Lun: 00
  Vendor: HL-DT-ST Model: BDDVDRW CT30N    Rev: WX02
  Type:   CD-ROM                           ANSI  SCSI revision: 05


[7.7.] Other information that might be relevant to the problem
       (please look in /proc and include all information that you
       think to be relevant):
It was brought to my attention that changes were made in kernel 3.5 that could be the source of the problem
with the M-Audio Fast Track Ultra.  Those changes are here:  https://github.com/torvalds/linux/commit/8fdff6a3


[X.] Other notes, patches, fixes, workarounds:  When running under current versions of AVLinux or KXStudio (both with kernel
versions older than 3.5), playback and record do work simultaneously, although latency is high.
Comment 1 grozzy 2015-08-30 18:26:52 UTC
The output of an ALSA information script was uploaded here while troubleshooting a week ago:  http://www.alsa-project.org/db/?f=f1436001041a68fada9f19d94fd5d4faceeb51f7
Comment 2 grozzy 2015-08-31 21:56:48 UTC
Whoops.  The kernel versions for AVLinux and KXStudio are 3.13 and 3.12.  I think the M-Audio Fast Track Ultra only works full-duplex with Jack in those distros, not directly with ALSA.
Comment 3 Victor Mataré 2016-02-27 00:00:27 UTC
I have the exact same problem with an M-Audio FastTrack C400 on a more recent kernel: 4.3.5-300.fc23.x86_64
Comment 5 Raymond 2016-02-27 09:57:40 UTC
(In reply to Victor Mataré from comment #3)
> I have the exact same problem with an M-Audio FastTrack C400 on a more
> recent kernel: 4.3.5-300.fc23.x86_64

https://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/commit/sound/usb?id=76f74bca73ec8210c6b04559445982907ad1b0a6

Seem only support 6 channel playback and 4 channel capture
Comment 6 François Jacques 2018-04-08 12:57:36 UTC
Victor: I think a separate bug that refers to this one would be useful for people who might have the same sound interface as you. Makes tracking easier, too!

My two cents:

A bit of googling led me to find that Clemens Ladisch thinks the FTU is indeed duplex capable. At least it appears it was at some point, perhaps before the aforementioned commit.

https://sourceforge.net/p/alsa/mailman/message/30468203/

So it seems there's really a bug in the driver and it has been acknowledged by another well established contributor of the project. 

Now what we'd need, I think, is some spelunking to other versions to check whether it was indeed functional *prior* to the new endpoint streaming model commit. At least that would confirm there was a regression between both codebases, at least for the FTU. Perhaps it needs some quirk adjustment or else?

I'm willing to try patches and experiment on my workstation. I'll try (don't hold your breath... may take a few days) to give it a shot with a Live CD with an older kernel.

I think the status can be changed to OPEN.
Comment 7 François Jacques 2018-04-08 12:59:19 UTC
Rectification: perhaps the bug isn't NOT in the driver but with the card itself. I typed this too fast.
Comment 8 Alexander Tsoy 2020-01-17 21:57:36 UTC
This is a common problem with all USB audio devices that use implicit feedback for synchronization. If you remove your device from set_sync_ep_implicit_fb_quirk() (sound/usb/pcm.c), it will work in duplex mode. But there will be pops and clicks during playback.