Video not in sync with audio

Hi. I’m new around here, so I don’t know, if I’m posting this in the right place.
If not, I’m sorry.
I have a concert in video (not DVD, just a normal avi file) in good quality, but the problem is that the audio is not synchronized with the video. Any ideas what should I do? Thanks.

Use Virtualdub to get the audio and video in synch again. There is a tutorial at Look in Guides > Virtualdub procedures > Manual synching

Thanks. I’ll try.