Comment 4 for bug 375988

This is happening to me too, but rather than restart firefox all the time I started using Pandora Radio (long-running flash w/ sound, the perfect candidate to be messed up by this) in Konqueror. It has the exact same problem, getting all messed up after a while, but I can restart it without affecting firefox :)

So: this affects konqueror too, and is thus not a firefox-only issue.