According to Rodrigo Rivas:
One last idea. Maybe the gnome-settings-daemon is playing dumb with your
sound. I think you can disable the sound plugin of g-s-d using dconf
(org.gnome.settings-daemon.plugins.sound.active).
I tried
dconf write org/gnome/settings-daemon/plugins/sound/active false
I don't know if that will affect also to the GDM greeter, but it is worth
trying it.
It had no effect, either in the greeter or in GNOME itself.
As a last resort you could also try renaming
"/usr/lib/gnome-settings-daemon-3.0/libsound.so" and see what happens.
Strangely, this also has no effect at all. Once GDM starts, the master
volume is still zeroed out and muted. I say zeroed out and muted because
I must run alsamixer, turn up the master volume and then unmute it in
order to get the sound working again, although
sudo systemctl start alsa-restore
also does work, since the volume was previously saved using
sudo systemctl start alsa-store
while the volume was at the proper level. At this point, I am totally
stumped. The computer I had that died used a SoundBlaster Live Value,
and although the sound started out muted, restoring the alsa volumes
always worked as expected. However, on this machine with the Intel
onboard sound, nothing seems to keep the volumes from muting whenever
GNOMe and GDM start.
~Kyle
