Audio out of sync when using LAME ABR

[muffinman123]

in virtualdub, now I have heard there's a problem with this when I searched it, but I couldn't understand what caused the problem. can someone explain if it's virtualdub specific or if it's something else?

[hech54]

9 times out of 10, the few times I've had "sync issues" in editing programs it was caused by the source material.

[muffinman123]

source materiel have no sync issue. I encoded the same video with cbr and every thing was fine.

[filmboss80]

I encoded the same video with cbr and every thing was fine.

And there you have your solution. Always use CBR (Constant Bitrate) to keep your audio in sync.

[davexnet]

There is a way to fix it. Open the converted avi. Set video and audio to direct stream copy.
File / save wav.
When the file is saved, modify the extension to mp3.
Audio/audio from another file (select the mp3)
file/save as avi (save as a new avi)

This problem occurs because Virtualdub writes standard CBR headers the first time the avi is created.
It does this because it doesn't know that you chose ABR in the audio encoder settings and defaults to CBR header.

However, the process above detects the vbr/abr and adjusts accordingly.