Audio Sync Solution!!
A workaround for Audio sync problems. Open two movie windows say W1 and W2. Follow these steps!!!
1) Minimize W1.
2) Drag the video of W2 a few seconds (usually to no. of seconds you assume the audio lag is!).
3) Mute and pause the video in W2.
4) Wait for the audio in W1(minimized) to sync the lips of the character speaking in the muted/paused window W2.
5) Play it when needed!!
6) One word Solution:: Sync the audio from the back(W1) with the video of the front(W2).