I have a DIVX AVI which has perfect sound/video sync for about an hour, and then, toward the end, there is a brief pop or snap in the audio, after which the sound/video are a little out of sync. If I can somehow cut out that pop from the audio track, or insert blank space in the soundtrack. I believe the sync will be fine. Right now I'm not sure if the audio is ahead of the video or behind it. The sync problem does not get worse gradually. It is constant after that one point.

I'm currently using TMPGEnc to export the audio and video as elementary streams. I will soon have an .m2v, .mpa, and .wav files. Any strategies on editing the sound and recombining would be appreciated!

Thanks!