Silly of me to look everywhere but in the right place.
I now have sound and video in VLC and MPlayer. However, now Thunderbird does not run. Here is what I get when I try to run it from the command line:
ALSA lib pcm_dmix.c:1008:(snd_pcm_dmix_open) unable to open slave
/usr/lib/thunderbird-2.0.0.23/run-mozilla.sh: line 131: 5538 Segmentation fault /usr/bin/soundwrapper "$prog" ${1+"$@"}
[edit] With Pulse Audio enabled in MCC, sound works but Thunderbird does not. When it is disabled, Thunderbird works but there is no sound.
I recently installed Linux Mint on a friend's computer. To get things moving it was necessary to remove Pulse Audio completely. Could that be the solution of my problem? If it is, how do I go about it?