Hi, sometimes I need to remux from mp4v2 to mkv (for my standalone player). But it seems Avidemux is more error-tolerant when muxing into mp4v2, because when muxing to mkv I sometimes get the famous "Too short" crash message.
It's not a very big issue, but I would appreciate is there is a simple solution.
I also noticed then when this remuxing job works, it gives audio desynchronization (audio 4 sec too short). Same result when I did an audio downmix reencoding, with what I supposed was a "zero error" file: h.264+AC3 6channels.avi -> h.264+AAC.mp4
So I guess when remuxing or reencoding, bad video/audio frames are skipped and cause desynchronization.