Fixing audio video synch problems can be done in various ways depending on the cause of the synch problem.
1. When the audio starts later than the video does OR the audio ends earlier than the video does, you can try editing the audio and re-encoding it with the video again. By this I mean the audio is completely CUT, and not pending. This means you will have to have a program that lets you save a WAVE file from a video file and a program that let’s you edit wave. If you own a copy of Nero Burning software, there is a good and simple wave editor in there. Virtualdub will help you strip the audio from avi and mpeg files. In the end, this method means that after setting it straight you will loose some audio.
2. When the audio starts later than the video does OR the audio ends earlier than the video does, and it is not CUT but pending: you probably have an audio sampling problem. Lower sampling rates then the original create slower audio, higher sampling rates then the original create faster audio. To use this method to try to sync the audio and video again, please take a look at this article. It explains how to convert sample rates. Only remember you must use NEW RATE to actually ‘speed the audio’ up or down.