[GRLUG] strange audio levels problem
jtr at jrichards.org
Tue Jun 21 20:17:28 EDT 2011
On Tue, Jun 21, 2011 at 02:58:21PM -0400, Michael Mol wrote:
> On Tue, Jun 21, 2011 at 2:25 PM, John-Thomas Richards <jtr at jrichards.org> wrote:
> > 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 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.
> >> 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).
> That they're random seems very, very strange. That almost feels like
> there's an uninitialized variable somewhere that's getting used in
> calculating what to set levels to. Either that, or there are multiple
> mixer-aware apps trying to restore sound preferences at the same time,
> and they're not being brought up in a consistent sequence.
> One thing to try:
> Switch to using a custom X session for some diagnostics. Rather than
> launching a full wm of any kind, just launch xterm. (Not konsole or
> gnome-terminal or anything like that)
Haven't used twm in a decade or so. twm at 1920x1080 looks a lot like
twm at 800x600. :-)
> If Pulse is running with the ALSA hook enabled, then any app which
> accesses ALSA for playback will launch Pulse, assuming Pulse has its
> configuration cookie lodged with your running X session. Once you boot
> into an X session which only has an xterm, you should be in as clean
> an X environment as is possible. Run 'ps' and verify the Pulse daemon
> isn't running. Now use alsamixer to check your levels.
alsamixer doesn't show the soundcard; it shows a "dummy" sound level at
> 1) Run ps and verify the Pulse daemon isn't running.
> 1a) If it is running, then something must have launched it prior to
> your user session launching, and left it up. This is bad; The
> PulseAudio folks strongly disrecommend using system-wide Pulse
> daemons, for security reasons. I also don't know how to go much
> farther in checking Pulse configurations in that kind of a setup.
> 1b) If it is not running, use alsamixer to check your card's audio
> level. (Since I have Pulse handle ALSA apps, and have the Pulse
> wrapper as my default sound device, I generally have to specify the
> card using something like 'alsamixer -c0')
> 1b1) If your levels are where you recall them being from having used
> alsactl-store, then, well, good. That means the problem more likely
> rests with conflicting apps or applets being launched as part of your
> user session.
> 1b2) If not, try having alsactl restore the values that it believes
> were saved. Check those.
> 1b2a)If those aren't what you expect, then you've probably got
> something in your shutdown cycle changing your ALSA settings and
> storing them.
> 1b2b)If alsactl's restore gave the values you expected, then the
> problem is between your login and your bootup. Some time in your init
> cycle between the first alsactl restore and when you got your desktop
> session (here, I'd wager the problem sits with xdm, kdm, gdm, whatever
> you're using) is where things got messed up.
Since the card doesn't show up, I installed xdm and wdm to see what is
loading pulse. Openbox is loading it. Twm does not. gdm3 could be,
but even if it is not Openbox is.
> >> 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.
> Yeah, I hear you. I was stuck in a similar boat for a while earlier
> this year. I discovered that if I visited a website which used flash
> prior to using some other sound app (such as launching pavu-control),
> then Flash would latch on to OSS. I had to switch to setting up an
> ALSA device for pulse, and made that device default, and that helped.
> Between that and learning more about the apps I was using, I got
> things stable. The greatest annoyances I've had since are discovering
> apps I want to use which *only* support OSS.
> Then I switched to Gentoo+KDE a month or so ago, and Pulse worked
> cleanly out of the box.
Well, that's not happening (Gentoo or KDE). :-) I have a decade
invested in learning Debian; I've no desire to learn a new distro just
to get sound working. It'll happen, even if it takes time. I really
appreciate the help and direction.
The moment a person forms a theory, his imagination sees, in every
object, only the traits which favor that theory.
Thomas Jefferson (1743-1826)
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