I thought that's normal till I play video tutorial (about After Effects) on other web ///
no sound from my After Effects CS5 ,no matter I play mp3 / .MOV / MPEG 4 / AVCHD
I even click the AUDIO panel out and adjust the db level,useless
I confirm that I have not muted the screen
But the sound comes out in Premiere Pro when I use Dynamic link,
after I worked on the files in A.E
....and in addition to reading the link Todd posted, it would probably make much more sense to post a few specs of your hardware, so someone could at least take a guess at what might be going on. You know, not much point to just saying that something doesn't work when we cannot possibly have the slightest clue about your specific audio hardware and its settings. Could be anything from bad drivers to genuine problems in AE, but who's to say?