An annoying little problem I ran into the other day:
- After Firefox 3b5 and flash locked up the screen, I had to force power cycle.
- On reboot, the master audio control showed it muted.
- On un-muting, no luck. The audio was completely absent.
- I re-installed the alsa driver.
sudo apt-get install alsa-base (it prompted me to insert the 8.04 alternate DVD)