This is an issue that I'm curious about.

I have an avi file that was initially difficult to play because it was H264 video + Ogg Vorbis 3+. It took me forever to get the audio to play properly. Since I plan to distribute the file I thought it might be more user friendly if the audio was in mp3 format.

So, I processed the audio in VirtualDub to mp3, and remuxed it into an avi format with the original video. The resulting file had horribly out of synch audio. Near the beginning of the file it was off by around 12 seconds, but towards the end "only" 4 seconds - not something I think is fixable by shifting the audio sych around.

I then used AVIMUX and the resulting avi was perfectly in synch and exactly like the original.

I'm curious as to why VDUB fails at this task? Perhaps there is something I don't understand about remuxing with VDub. I loaded the video file and set stream to direct copy, then I selected the audio "Browse for audio" in the audio section, direct stream copy, then saved avi.

Thanks for any suggestions!