Bug 70821 - White noise / static from Headphones (ASUS N550JV)
Summary: White noise / static from Headphones (ASUS N550JV)
Status: NEW
Alias: None
Product: Drivers
Classification: Unclassified
Component: Sound(ALSA) (show other bugs)
Hardware: x86-64 Linux
: P1 normal
Assignee: Jaroslav Kysela
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2014-02-19 00:00 UTC by iateyourgranny
Modified: 2014-02-26 01:24 UTC (History)
1 user (show)

See Also:
Kernel Version: 3.13.3
Tree: Mainline
Regression: No


Attachments
maxxaudio on windows (170.49 KB, image/jpeg)
2014-02-23 17:07 UTC, iateyourgranny
Details

Description iateyourgranny 2014-02-19 00:00:43 UTC
There is a constant slightly-squeaky soft white noise coming from my headphones on all the versions of Linux I've tried on my laptop (Linux Mint 16, Archbang, Opensuse 13.1, Fedora 20). It seems that:
- if I *unmute* the microphone output on alsamixer, the squeakiness (which sounds like Tinnitus) goes away, although the white noise is still there.
- if I mute the headphone channel or the main channel, the noise goes away.
- the loudness of the noise is not affected by the volume level of any channel.
- the noise does not go away if I unplug my laptop charger.
- the noise cannot be heard from the laptop speakers.

Also, my laptop is (was) a dual-boot with Windows 8.1. There was a similar problem with the headphones on Windows (although slightly less louder if I remember right). The problem went away after I updated my audio driver to Realtek High Definition Audio 6.0.1.7083 from the ASUS N550JV support website.

Things that may be relevant:
- The sound card is Realtek ALC668, I believe.
- This laptop has the headphones and mic jack in the same.. jack.
- As an aside: ALSA selects the HDMI output (with non-changeable zero SPDIF volume levels) as default, even though it doesn't play anything. It also strangely calls both audio outputs as snd_hda_intel, which can lead to confusion in selecting the default sound card on the ALSA config file.
Comment 1 Raymond 2014-02-20 10:18:27 UTC
our powerful speakers create immersive sound, tuned by the ASUS Golden Ear team. The quad-speaker array shapes sound and ensures best-reproduction and delivery. Beamforming and crosstalk cancellation join Head-Related Transfer Function (HRTF) technology to clear up audio, remove interference

what is quad speaker array ?

do it have four internal speakers using 4 channels if it can use crosstalk cancellation and HRTF ?
Comment 2 Raymond 2014-02-20 15:09:43 UTC
Node 0x0e [Audio Mixer] wcaps 0x20010b: Stereo Amp-In
  Amp-In caps: ofs=0x00, nsteps=0x00, stepsize=0x00, mute=1
  Amp-In vals:  [0x00 0x00] [0x80 0x80]
  Connection: 2
     0x04 0x0b

does it help if you mute the input from audio mixer 0x0b into node 0x0e  ?
Comment 3 Raymond 2014-02-22 13:07:23 UTC
https://www.asus.com/au/Notebooks_Ultrabooks/N550JV


seem four speakers at the front bottom of the laptop
Comment 4 iateyourgranny 2014-02-22 23:56:00 UTC
Yes, it's four speakers and an external subwoofer. Not sure about muting the audio mixer node.
Comment 5 iateyourgranny 2014-02-23 00:01:43 UTC
If it helps, there was a recent bug concerning the same sound system, where the subwoofer wasn't working. It was fixed in 3.13-rc1:

https://bugzilla.kernel.org/show_bug.cgi?id=65091
Comment 6 Raymond 2014-02-23 00:33:51 UTC
do you mean four speakers only use stereo ?

do all four speakers playback sound ?

do you mean the two speakers at the left playback the left channel and the two speakers at the right playback the right channel ?
Comment 7 Raymond 2014-02-23 12:52:50 UTC
how do the speakers works windows ?

when audio wizzard 

1) music mode
2) movies mode
3) record mode
4) gaming mode
5) speech mode


Do maxxaudio support 5.1 or 7.1 downmix playback ?


maxxstereo 

are there any differences of the sound in four speakers in wide mode and the other modes ?
Comment 8 iateyourgranny 2014-02-23 17:07:50 UTC
Created attachment 127171 [details]
maxxaudio on windows
Comment 9 Raymond 2014-02-24 01:25:58 UTC
http://www.maxx.com/technologies/maxxaudio/

 MaxxVolume uses a powerful combination of high level compression to increase RMS levels, low level compression to increase the clarity of soft sounds, and noise gating to eliminate signal and system noise



does the sub woofer need low pass filter ?
Comment 10 iateyourgranny 2014-02-24 02:28:50 UTC
It seems you can adjust the low cutoff frequency with the maxxaudio control panel, so I think it uses a low pass filter. Here's specifics: http://www.maxx.com/objects/PDF/MaxxAudio%20Master%20for%20Asus%20N-Series%20User%20Guide.pdf

I would guess that the sub woofer needs a low pass filter, since when I got it working on linux, you could hear more than just the bass.
Comment 11 Raymond 2014-02-24 03:58:34 UTC
are there any difference in surround 2.1 

http://git.alsa-project.org/?p=alsa-lib.git;a=commitdiff;h=57b5076c30b3453ee843912c0aeb3df8dbee3f68;hp=326c6802e49e5499e16cf141e1cdb0360fce14aa

1) http://www.asus.com/ROG_ROG/G75VW/

SonicMaster Lite powerful audio with built-in subwoofer

vt1802 is only 4 channels 


2) http://www.asus.com/Notebooks_Ultrabooks/N56VZ/

alc663 is 6 channels 

SonicMaster Premium with stereo speakers with external subwoofer 



3) your N550JV

SonicMaster Preium with quad-speaker array and external subwoofer 

alc668 is 6 channels
Comment 12 Raymond 2014-02-24 11:20:57 UTC
do you mean quad speaker array are working as same as in windows ?



http://lists.freedesktop.org/archives/pulseaudio-discuss/2014-February/019996.html

pulseaudio don't provide low pass filter for LFE channel

you also need hack in driver if surround21 need 6 channel if quad speaker array only need stereo
Comment 13 Raymond 2014-02-26 01:24:59 UTC
you can try automute via amp instead of pinctl 

https://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/commit/?id=493a52a9b6645f61954580c7d4bd52fa62110934

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