Yesterday I updated to QuickTime 6.4, and it worked fine. Today, though, QT audio playback doesn't work at all. In QuickTime player (and finder previews, safari, etc.) it just plays through movies (and even sound files) without making any sound. (Other sounds, like finder alerts, still work, so I know my sound system works) Also, in iTunes, when I try to play a song, it changes everything as if it's playing, but the "remaining time" doesn't count down (so it's not playing through the song file at all). It just sits there until I hit the pause button. There's no strange messages in the console, and since it never actually crashes, there's no crash log... Anybody have any ideas?