I cannot upload the fresh amixer.org, amixer.pulse and pulseaudio log files (internal server error). Either use the ones attached to mailinglist post or email me for the fresh files.

There are other people on ArchLinux that seem to be affected.

http://archlinux.2023198.n4.nabble.com/GDM-and-or-PulseAudio-mute-my-sound-td4659822.html

https://bbs.archlinux.org/viewtopic.php?id=130201

Pulseaudio seems to remove the "analog-output" path, because it appears to be a subset of "analog-output-mono". "analog-output-mono" is then chosen as the active path, and it mutes the Master element, because it thinks that Master Mono (also available) is the right element to use.

It appears that Master Mono has volume control for two channels. That seems strange, I wonder if this is an alsa bug? If it had only one channel, as would be logical, then I believe the "analog-output" path wouldn't be considered a subset of "analog-output-mono", and things would work for you.

But there's another odd thing: why is "analog-output-mono" path part of the "analog-stereo" mapping at all? That doesn't make sense to me. Removing the path from the "analog-stereo" mapping should also make things work for you.

So, try editing /usr/share/pulseaudio/alsa-mixer/profile-sets/extra-hdmi.conf. There's this section:

[Mapping analog-stereo]
device-strings = front:%f hw:%f
channel-map = left,right
paths-output = analog-output analog-output-speaker analog-output-desktop-speaker analog-output-headphones analog-output-headphones-2 analog-output-mono analog-output-lfe-on-mono
paths-input = analog-input-front-mic analog-input-rear-mic analog-input-internal-mic analog-input-dock-mic analog-input analog-input-mic analog-input-linein analog-input-aux analog-input-video analog-input-tvtuner analog-input-fm analog-input-mic-line analog-input-headphone-mic
priority = 10

Remove analog-output-mono from the paths-output line.

(In reply to comment #3)
> 
> But there's another odd thing: why is "analog-output-mono" path part of the
> "analog-stereo" mapping at all? That doesn't make sense to me. Removing the
> path from the "analog-stereo" mapping should also make things work for you.
> 
> So, try editing /usr/share/pulseaudio/alsa-mixer/profile-sets/extra-hdmi.conf.
> There's this section:
> 
> [Mapping analog-stereo]
> device-strings = front:%f hw:%f
> channel-map = left,right
> paths-output = analog-output analog-output-speaker
> analog-output-desktop-speaker analog-output-headphones
> analog-output-headphones-2 analog-output-mono analog-output-lfe-on-mono
> paths-input = analog-input-front-mic analog-input-rear-mic
> analog-input-internal-mic analog-input-dock-mic analog-input analog-input-mic
> analog-input-linein analog-input-aux analog-input-video analog-input-tvtuner
> analog-input-fm analog-input-mic-line analog-input-headphone-mic
> priority = 10
> 
> Remove analog-output-mono from the paths-output line.

I tried this after deleting my ~/.pulse dir (I am not sure if that was necessary, I guess I just assumed it was). Now gnome session starts up muted but this time you can actually see a muted speaker symbol in the notification area. Then it is simply a matter of raising the volume with the basic volume control in the notification area. The settings seem to be automatically recovered when I reboot and login again.

Also, Jan Steffens replied to my downstream bug report [1], he suggested playing with pavucontrol/gnome-settings. I had tried this before.

After his comment I had another go with pavucontrol and started clicking everything and suddenly I start getting sound again.

I reset my .pulse dir to find out what made the difference (delete .pulse from console session and reboot, login to gnome).

It turns out I have to switch output "connector" (in gnome) or "port" (pavucontrol) from "Analog Mono" to "LFE on seperate mono output" (whatever that is!).

Now pulseaudio seems to keep the "good" setting where sound can be heared. It seems that after changing this one setting, the master channel that was zeroed and muted is now maxed and unmuted.


[1] https://bugs.archlinux.org/task/31469

(In reply to comment #3)
> It appears that Master Mono has volume control for two channels. That seems
> strange, I wonder if this is an alsa bug? If it had only one channel, as would
> be logical, then I believe the "analog-output" path wouldn't be considered a
> subset of "analog-output-mono", and things would work for you.
> 

It seems the master channel on my "Intel 82801AA-ICH"/"SigmaTel STAC9700,83,84" on alsamixer (it's actually a virtualised device on VirtualBox) has left and right sub channels that can be adjusted with Q-Z and E-C respectively.

(In reply to comment #5)
> (In reply to comment #3)
> > It appears that Master Mono has volume control for two channels. That seems
> > strange, I wonder if this is an alsa bug? If it had only one channel, as would
> > be logical, then I believe the "analog-output" path wouldn't be considered a
> > subset of "analog-output-mono", and things would work for you.
> > 
> 
> It seems the master channel on my "Intel 82801AA-ICH"/"SigmaTel STAC9700,83,84"
> on alsamixer (it's actually a virtualised device on VirtualBox) has left and
> right sub channels that can be adjusted with Q-Z and E-C respectively.

I couldn't tell you if you if this was a bug in alsa or not. Is there a "standard" way for driver writers/device manufactures to arrange mixer channels on a device?

If you need help reporting this to alsa let me know.

Thanks.

(In reply to comment #6)
> (In reply to comment #5)
> > It seems the master channel on my "Intel 82801AA-ICH"/"SigmaTel STAC9700,83,84"
> > on alsamixer (it's actually a virtualised device on VirtualBox) has left and
> > right sub channels that can be adjusted with Q-Z and E-C respectively.
> 
> I couldn't tell you if you if this was a bug in alsa or not. Is there a
> "standard" way for driver writers/device manufactures to arrange mixer channels
> on a device?
> 
> If you need help reporting this to alsa let me know.

If by "this" you mean that the Master element has two channels, that's not a bug at all. What may or may not be a bug is that the Master Mono element has two channels too. But in any case, I don't think alsa needs to be fixed here even if it's broken.

What I'd like you to do is to test the change in extra-hdmi.conf that I suggested. If it fixes the problem, then I can write a patch, and hopefully this problem won't bug people any more.

Changing the port to "LFE on seperate mono output" is only a workaround, not a fix. The "LFE on seperate mono output" port is meant for cases where a laptop has a separate subwoofer speaker that is handled in a bit strange way: there's no separate subwoofer channel in the audio stream that pulseaudio writes to alsa, but there's a separate volume element (Master Mono) for the subwoofer.

(In reply to comment #7)
> If by "this" you mean that the Master element has two channels

Yes that is what I meant.

> What may or may not be a bug is that the Master Mono element has
two channels too

Yes that does sound a little weird.

> What I'd like you to do is to test the change in extra-hdmi.conf that I
> suggested.

I did try this the result where in my reply to comment #3:

>> (In reply to comment #3)
>> I tried this after deleting my ~/.pulse dir (I am not sure if that was
>> necessary, I guess I just assumed it was). Now gnome session starts up muted
>> but this time you can actually see a muted speaker symbol in the notification
>> area. Then it is simply a matter of raising the volume with the basic volume
>> control in the notification area. The settings seem to be automatically
>> recovered when I reboot and login again.

> If it fixes the problem, then I can write a patch, and hopefully
> this problem won't bug people any more.

I guess your "extra-hdmi" fix improves matters but there are still a few issues. With the default settings the speaker-test program still produces no audible sound. The master channel is *still* muted and zeroed. However, the gnome3 volume control applet also shows muted and "very low". So the level can be corrected easily by a regular user. If I look in alsamixer on card0 the master channel is still zeroed and muted while the master mono is maxed and unmuted.

I think I'd prefer the volume to default to maxed and unmuted on the master channel by default.

Created attachment 66938 [details]
default amixer levels for card 0 after modifications to extra-hdmi.conf

(In reply to comment #8)
> > What I'd like you to do is to test the change in extra-hdmi.conf that I
> > suggested.
> 
> I did try this the result where in my reply to comment #3:
> 

This should have read:

I did try this. The results were in my reply to comment #3:

Sorry for missing the point that you had already tested my suggestion. It sounds that the fix works fine. The default behavior of volume being low and mute being on most likely happens because if the user hasn't set any particular volume (which is the case if you cleared ~/.pulse), then the volume is initialized to whatever volume alsa is currently having. Alsa should have a sane default volume, but in your case maybe the previously-broken pulseaudio behavior had left the alsa mixer muted and at a low volume.

Patch sent to the mailing list: http://thread.gmane.org/gmane.comp.audio.pulseaudio.general/14348

Fixed: http://cgit.freedesktop.org/pulseaudio/pulseaudio/commit/?id=9e4229cfe03d441a01a0f1bd02972936048ae85d