Sound in Ubuntu Hardy Heron just stopped working. I think my sound card is not recognized because I get the message [../../../src/audio.c:267] error: Unable to set up output device! Constraints: 44100, 22050 or 11025Hz. when I try mpg123 <somemp3file> on the console. This can be fixed by a reboot, but why should I have to do it every time this happens? Also, video files are shown as playing in Totem, but they actually are not playing.

Anybody has an idea about this?