Pulse Audio

[Kyle]

GNOME depends on Pulseaudio. You can manually break Pulseaudio so that
it doesn't work correctly, usually by symlinking /bin/true, but that can
cause problems when packages are updated.

Your best bet, unless you have something like a USB headset that may or
may not always be plugged into the system, would be to connect
Pulseaudio through the Alsa Dmix plugin. The problem with doing this is
that Pulseaudio can no longer automatically detect hotplugged devices
such as USB headsets, as you will need to stop it from grabbing your
main hardware via udev. If you don't have a problem with this method,
instructions are available at
https://wiki.archlinux.org/index.php/PulseAudio#ALSA.2Fdmix_without_grabbing_hardware_device
This is in the Arch Linux wiki, but should work correctly in Debian as
well. Hope this helps.
~Kyle
http://kyle.tk/
-- 
"Kyle? ... She calls her cake, Kyle?"
Out of This World, season 2 episode 21 - "The Amazing Evie"