If your video and audio is out of sync in more players, this is a fault in the movie-file itself, which you could re-sync using i.a. VirtualDub, VirtualDubMod, Nandub or even an application like "AVI File info"
http://bsplayer.com/forum/viewtopic.php?p=20219#20219
(Edited to repair the link which wasn't working any more)