Hi. I am currently running FC 4 and i have a sound problem. The thing is that i can, for instance, run kaffeine and i play mp3s perfectly, but, if i close kaffeine, completely, and try to view something with sound on firefox, i get video but no sound. I remember that sometimes i restarted firefox or the computer, and i could play music, apparently, i need to close or shutdown something if i want to change the application playing sound.

Does anybody have an idea how to fix this?