[alsa-devel] Bug 48381 - [Regression][Bisected]Sound gets permanently muted a few minutes after booting
david.henningsson at canonical.com
Wed Oct 10 15:20:50 CEST 2012
On 10/10/2012 02:59 PM, Da Fox wrote:
> Hi all,
> Since the official bug-tracker at
> https://bugtrack.alsa-project.org/alsa-bug/ seems to be down (and
> moreover this appears to be a kernel bug), I have filed a bug at the
> kernel's bug-tracker last week (
> https://bugzilla.kernel.org/show_bug.cgi?id=48381 ). However, it seems
> to have gone unnoticed thus-far.
> Quick summary of the issue:
> After a while of inactivity the sound-card seems to go into a sort of
> power-saving mode (you can hear a faint 'pop' from the speakers).
> Before the sound would automatically turn back on again as soon as a
> program attempted to play sound. However now it seems that after
> resuming from the power-saving mode the driver thinks that there is
> always a headphone connected, even when it is not. I think this is
> what happens because toggling the 'Auto-Mute Mode' (setting it to
> 'Disabled') in alsamixer allows the speakers to produce sound again.
> This is all on a laptop (please see the linked bug report for more
> detailed hardware description).
> Would a developer please take a look at it? I have bisected the issue
> down to a commit made by David Henningsson and/or Takashi Iwai:
> 80c8bfbe76869bfd6bdf3d260d316e7a32f318c3 is the first bad commit
> commit 80c8bfbe76869bfd6bdf3d260d316e7a32f318c3
> Author: David Henningsson <david.henningsson at 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 at canonical.com>
> Signed-off-by: Takashi Iwai <tiwai at suse.de>
> :040000 040000 7a954b731bef80cee731763521f64a424a7058a0
> 7d176b02ebb4553b0b0f97d200f7527cb69c122a M sound
> If any additional information is required please let me know.
Thanks for the heads up. I would need the following additional information:
1) One alsa-info taken during playback through internal speakers, when
the internal speakers are working, and
2) One alsa-info taken during playback through internal speakers, when
the internal speakers are not working.
(See https://wiki.ubuntu.com/Audio/AlsaInfo if you don't know what
If you're using PulseAudio for playback, please also include the output
of "pacmd list" in the above two scenarios.
David Henningsson, Canonical Ltd.
More information about the Alsa-devel