Hey, I muxed two AVI files using AVI-Mux, and for some reason the audio is out of sync with the video in the final file after being muxed.
Both files are in perfect sync individually.

However, the sync is not constant, it only gets out of sync near the last 5 minutes.

Ive read online on some solutions, such as changing the framerate. When I change the framerate of the video, the out-of-sync portion DOES resync, but the beginning of the video that was originally in sync starts to get a little out of sync.

Does anybody have any solutions? Is there any tool or something I can use to edit a video and fix the sync after a certain time frame?