Hi I'm having a problem... the sound has stopped working on all internet stuff. Youtube, myspace... anything like that, there is no sound... but would still works in iTunes and VLC, DVD player, etc. Frustratingly, it doesn't work in ANY browser, (well, safari, firefox and IE). Any ideas? I can't find a setting anywhere for internet sounds, but this is the first time I've really hd a problem of this nature with my mac. Thanks!