lip sync, lip sync, lip sync.
This can be a real pain. If you movie starts in sync and moves out of sync well into the movie it can mean that the audio and video streams are different lengths. There are a number of ways of fixing it.
Get a copy of avi file info by terabit software. this is a little utility that allows use to stretch or strink the audio to fit.
also checkout
manual lipsyncing on
and this thread [/url]
hope it helps