Comment 19 for bug 432660

I am experiencing a similar problem. I am using external speakers which have a light on top which is normally blue but turns red when audio is muted. When I start my machine, the light is blue until gdm starts. When gdm starts the speaker light goes red.

When I login to my user account and start the Gnome ALSA Mixer program it shows me the Master volume and Front channel volume on the "Realtek ALC889A" tab are muted. Also, on the "USB Mixer" tab, PCM volume has been set to almost zero and the channel muted. I have to reset all four of these settings every time I login. If I log out, the speaker light goes from blue to red once more. I login again and have to reset all four settings.

I ran the tests listed above re: killing pulseaudio, setting autospawn=no, and running pulseaudio -vvvv. Doing this as my normal login user was fine. The start of pulseaudio did not change any of my mixer settings. The problem is with something that the start of (or return) to gdm which changed the audio mixer settings.