Created attachment 102890 [details]
Screenshot

Notice how the popup still shows one wave, something that is not true when volume is all the way down (it shows the muted icon in that case).

Actually, it's possible for the volume bar to be (very close to) zero, and sound still not being muted, so the screenshot doesn't necessarily show a bug.

(In reply to comment #2)
> Actually, it's possible for the volume bar to be (very close to) zero, and
> sound still not being muted, so the screenshot doesn't necessarily show a bug.
> 

But the pressing volume down should not set the volume to something bigger then 0 again...

I also have encountered this issue. Furthermore, using the media keys to adjust the volume will (seemingly) randomly adjust the left and right channels at different rates. Pressing the volume+ or volume- button one more time fixes this, making the channels equal volume.

Are you by any chance using the same hardware and/or ALSA driver?

snd_hda_intel here (and still happening with up-to-date gnome-cc.

Are you both using the composited version? Can you reproduce it with the non-composited one as well? Paul, what's your driver?

(In reply to comment #7)
> Are you both using the composited version?

For me, that would be a "yes". I seldomly  see the non-composite one, but I will try to reproduce it there as well.

I'm using the intel hda driver as well. No compositing here.

Created attachment 110063 [details] [review]
add some debugging output

Could you please apply this patch, run g-s-d with --no-daemon --debug, and post the output of when it happens?

Uhh, any idea what the package is in gentoo? Also, what is the command to run g-s-d?

Sorry, I just realized I am running gnome 2.20.3, and I don't have g-s-d installed.

(In reply to comment #12)
> Sorry, I just realized I am running gnome 2.20.3, and I don't have g-s-d
> installed.
> 

You have, it was part of gnome-control-center. I think I can test with the patch, but I have trouble reproducing this... Paul, did you find any indication what you actually have to do to reproduce this? Or is it mostly random for you, too?

** (gnome-settings-daemon-bak:31530): DEBUG: after: mute 0, vol 61, step 4
** (gnome-settings-daemon-bak:31530): DEBUG: before: mute 0, vol 61
** (gnome-settings-daemon-bak:31530): DEBUG: after: mute 0, vol 58, step 4
** (gnome-settings-daemon-bak:31530): DEBUG: before: mute 0, vol 58
** (gnome-settings-daemon-bak:31530): DEBUG: after: mute 0, vol 55, step 4
** (gnome-settings-daemon-bak:31530): DEBUG: before: mute 0, vol 55
** (gnome-settings-daemon-bak:31530): DEBUG: after: mute 0, vol 0, step 4 <----
** (gnome-settings-daemon-bak:31530): DEBUG: before: mute 0, vol 52
** (gnome-settings-daemon-bak:31530): DEBUG: after: mute 0, vol 48, step 4
** (gnome-settings-daemon-bak:31530): DEBUG: before: mute 0, vol 48
** (gnome-settings-daemon-bak:31530): DEBUG: after: mute 0, vol 45, step 4

I tested a bit, I couldn't really reproduce it but I guess this is related. I noticed some "flashing" now and then. Look at the marked line. The volume jumps to 0 without any reason. I guess you must be "lucky" to hit suck a 0-step.

When I cycle from max volume to min volume, or vice versa, using the multimedia keys, it will almost always happen at least once. Reaching max or min volume is not required, just an example of how frequently this occurs.

The first thing to check is whether the GStreamer, ALSA, or OSS audio backend is used.

For GStreamer, I'm pretty certain that this is a dupe of very a many gnome-volume-control and mixer-applet bugs where ALSA gives GStreamer bogus data, and GStreamer believes it.

See bug 518082, and bug 478498

Michael at least is using the gst backend, so I'm marking this as a duplicate.

*** This bug has been marked as a duplicate of 478498 ***