[alsa-devel] Issues and/or possible bugs in alsa

[Takashi Iwai]

At Tue, 24 Feb 2015 17:46:09 -0500,
Yomi Ogunwumi wrote:
> 
> Hello.
> 
> I seem to have run into a few issues with alsa.
> 
> First, when I plug my headphones into my laptop, sound continues to play
> out of the speakers and doesn't switch over to (or unmute) the headphones.
> Auto-Mute Mode is enabled in alsamixer. The same thing happens when I
> unplug the headphones, it doesn't switch over to the speakers. I have to do
> the same thing I described above, (no unmuting, I just have to turn up the
> volume for the speakers in alsamixer.)
> 
> Second. When I plug in these headphones, I can't use the internal
> microphone on this laptop, it mutes. (AFAICT)
> These headphones do not have a microphone built in, they're just an
> ordinary pair of headphones. However, I was given a workaround in #alsa on
> freenode. In order to use the laptop's internal microphone with my
> headphones plugged in, I have to do : sudo hda-verb /dev/snd/hwC1D0 0x22
> SET_CONNECT_SEL 6 — it works, but it isn't really ideal.
> 
> alsa-info is here : https://gist.github.com/Yomi0/9bfc3e72588cf8a35811
> 
> The first file in that gist is alsa-info with headphones and the second is
> without headphones.
> 
> Third. This is just a question. Is this :
> https://bugs.freedesktop.org/show_bug.cgi?id=86676 actually a pulseaudio
> bug, or is it an issue with alsa?
> I'm only asking since Raymond linked something that seemed to belong to the
> alsa project.

The alsa-info.sh output above shows the reads from the codec failed.
Could you try once to disable power-saving?  Set power_save=0 option
to snd-hda-intel module.

Note that power_save option might be changed dynamically by the system
(accessible via /sys/module/snd_hda_intel/parameters/power_save).  If
the problem is still seen, check the value there whether you still
really have 0 or it was changed by the system.

Restricting the power-save isn't a solution but helps understanding
the cause, at least.


Takashi