[GRLUG] strange audio levels problem

[John-Thomas Richards]

On Tue, Jun 21, 2011 at 01:11:57PM -0400, Michael Mol wrote:
> > On Tue, Jun 21, 2011 at 6:27 AM, John-Thomas Richards <jtr at jrichards.org> wrote:
> > I'm running LMDE (Linux Mint with Debian Wheezy).  I'm getting strange
> > behavior from my sound settings.  I save them via `alsactl store' at the
> > following levels:
> >
> > Master          Speaker         PCM
> > 80              100             100
> >
> > If I restart they will be changed to random levels.  For example, I just
> > rebooted and the settings are:
> >
> > 0 (muted) | 2 (muted) | 99
> >
> > Sometimes they will be:
> >
> > 40 (muted) | 0 (muted) | 100
> >
> > I store the levels as root.  This box is also running PulseAudio.  The
> > PulseAudio level is also often muted and at a low level (20 or 25 or
> > 40).  Any ideas?  Sound just seems to be far too complicated these days.
> > This almost (almost!) makes me wish for the OSS days.
> 
> 'alsactl store' will save your sound settings so that they get
> restored on bootup. That's reasonable and good.
> 
> Your problem is that PulseAudio is a per-user system, whereas ALSA is
> system-wide. Here's what's most likely going on:

This is helpful.

> 1) Your system enters its init sequence
> 2) Your system restores the ALSA settings saved by alsactl.
> 3) You log in
> 4) The first app to access PulseAudio (either directly or via the
> ALSA->Pulse wrapper library) will spawn the PA daemon.
> 5) The PA daemon will adjust its internal mixer levels, and the ALSA
> levels, as needed in order to satisfy whatever requests are made of
> it.
> 
> Step 2 is where things start to go wrong, step 5 is where they're
> going to go *really* wrong. In general, you're going to want ALSA
> configured to its maximum clean volume output. (For my sound chipset,
> this means loading up alsamixer and adjusting each level until each
> gain level reads '0').
> 
> Once ALSA is configured to a good normalized baseline at system start,
> your desktop session's sound daemon should behave better.

I've adjusted the gain levels to 0 and stored them.  I'm still getting
very strange and seemingly random levels.  I adjusted the levels and
restarted X and rebooted a number of times.  Here are my levels after
these restarts:  (Master | Speaker | PCM | Pulse)

 99  |  94  | 100/mute |  85
 91  |  94  |  99      |   9
  0  | 100  | 100      |   8
  0  |  94  | 100      |   8
  0  |  94  | 100      |   9
100  |   0  | 100      | 100
  3  |   0  |  98      |   9

If the Pulse levels are being adjusted at Step 5, I cannot figure out
what is accessing it.  I removed the sound applet from Cairo-dock (I'm
running Openbox) and have no sound apps loading at launch.  It seems
that if something is adjusting the levels it would do so consistently.
To rule out Openbox as the culprit I restarted X into GNOME a couple
times.  Same results (random).

> Two good links to go over if you're running Pulse, regardless of what
> distro you're using:
> https://wiki.archlinux.org/index.php/PulseAudio
> http://www.pulseaudio.org/wiki/PerfectSetup

These are good resources.  Unfortunately, I cannot find an answer to my
problem.  The closest I found is in the second article that suggests
running alsamixer to unmute sound.  I've already been doing that; I want
to avoid having to do so.
-- 
john-thomas
------
Talk sense to a fool and he calls you foolish.
Euripides

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