Bug 48381 - [Regression][Bisected]Sound gets permanently muted a few minutes after booting
[Regression][Bisected]Sound gets permanently muted a few minutes after booting
Product: Drivers
Classification: Unclassified
Component: Sound(ALSA)
All Linux
: P1 normal
Assigned To: Takashi Iwai
Depends on:
  Show dependency treegraph
Reported: 2012-10-04 21:48 UTC by da_fox
Modified: 2012-10-11 14:39 UTC (History)
1 user (show)

See Also:
Kernel Version: 3.6
Tree: Mainline
Regression: Yes

Dmesg after the issue has manifested (65.26 KB, application/octet-stream)
2012-10-05 14:54 UTC, da_fox
Output of alsa-info after a fresh boot of the system. Speakers verified to be working. (30.33 KB, text/plain)
2012-10-10 13:35 UTC, da_fox
Output of alsa-info after a few moments of inactivity. Speakers verified to NOT be working. (30.33 KB, text/plain)
2012-10-10 13:36 UTC, da_fox

Description da_fox 2012-10-04 21:48:46 UTC
After updating to kernel 3.6 (from 3.5) I noticed that my laptop speakers seemed to stop working a few minutes after booting. After some investigating I found that the headphone output still works. Also disabling the 'Auto-Mute Mode' with alsamixer makes the laptop's speakers generate sound again.
It seems that after a maybe a minute of inactivity the soundcard goes into a low-power mode (you can hear the speakers 'pop'). Perhaps after this the driver thinks that there is a headphone plugged in while it is not?

As long as there is sound being output the speakers keep working, this only seems to happen after a period of inactivity.

--- Steps to reproduce---
1) Reboot, to ensure that sound works.
2) Test that sound actually works from the built-in speakers, volume is on, nothing is plugged into the headphone jack (mplayer my_favourite_song.wav)
3) Wait a few minutes, with no sound
4) Try to output some sound again (mplayer my_favourite_song.wav)

--- Expected result ---
Sound eminates from the laptop's built-in speakers

--- Actual result ---

--- Hardware ---
I have a 'Dell XPS 15 (L502x)' laptop with:
00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05)
	Subsystem: Dell Device 04b6
	Flags: bus master, fast devsel, latency 0, IRQ 53
	Memory at f1c00000 (64-bit, non-prefetchable) [size=16K]
	Capabilities: [50] Power Management version 2
	Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit+
	Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00
	Capabilities: [100] Virtual Channel
	Capabilities: [130] Root Complex Link
	Kernel driver in use: snd_hda_intel

--- Bisection results ---
This was the output of the bisect:
80c8bfbe76869bfd6bdf3d260d316e7a32f318c3 is the first bad commit
commit 80c8bfbe76869bfd6bdf3d260d316e7a32f318c3
Author: David Henningsson <david.henningsson@canonical.com>
Date:   Mon Jun 4 09:33:51 2012 +0200

    ALSA: HDA: Create phantom jacks for fixed inputs and outputs
    PulseAudio sometimes have difficulties knowing that there is a
    "Speaker" or "Internal Mic", if they have no individual volume
    controls or selectors. As a result, only e g "Headphone" might
    be created for a laptop, but no "Speaker".
    To help out, create phantom jacks (that are always present,
    at least for now) for "Speaker", "Internal Mic" etc, in case we
    detect them.
    The naming convention is e g "Speaker Phantom Jack".
    In order not to pollute the /dev/input namespace with even more
    devices, these are added to the kcontrols only, not the input devices.
    Signed-off-by: David Henningsson <david.henningsson@canonical.com>
    Signed-off-by: Takashi Iwai <tiwai@suse.de>

:040000 040000 7a954b731bef80cee731763521f64a424a7058a0 7d176b02ebb4553b0b0f97d200f7527cb69c122a M	sound

I tried to revert this commit on top of v3.6, but it would not apply.
Comment 1 da_fox 2012-10-05 14:54:46 UTC
Created attachment 82371 [details]
Dmesg after the issue has manifested
Comment 2 da_fox 2012-10-10 13:35:17 UTC
Created attachment 82801 [details]
Output of alsa-info after a fresh boot of the system. Speakers verified to be working.
Comment 3 da_fox 2012-10-10 13:36:02 UTC
Created attachment 82811 [details]
Output of alsa-info after a few moments of inactivity. Speakers verified to NOT be working.
Comment 4 Takashi Iwai 2012-10-11 14:39:05 UTC
The fix patch by David was merged yesterday and included in the pull request to Linus now.

commit f7f4b2322bf7b8c5929b7eb5a667091f32592580
Author: David Henningsson <david.henningsson@canonical.com>
Date:   Wed Oct 10 16:32:09 2012 +0200

    ALSA: hda - do not detect jack on internal speakers for Realtek

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