Lagging audio when converting DivX/XviD to MP4

[prufrockian]

I use Videora iPod Converter to convert DivX and XviD formatted AVI's to MP4 for playing on my iPod. I have tried 3GP Converter which has worked flawlessly, except for not allowing me to specify frame size, so all widescreen videos are stretched out. Videora iPod Converter lets me do this, but I've found a lot of times that the audio lags as the video goes on... like it starts fine, but it gets progressively off until it's about 2 seconds slow by the end of the video. I extracted a WAV from the original and re-created the AVI using CBR audio, but it didn't fix the problem. Anyone have any suggestions on how to stop the audio from lagging? Or also, anyone know how to specify frame size in 3GP Converter/know of a different program that lets you do this for AVI to MP4 conversion?

[Baldrick]

You could try SUPER 1.

Or can't you change the frame size in some config files in 3gp converter? or do you mean adding black borders/keep aspect ratio? you could do it with avisynth.

[prufrockian]

I've tried using an AviSynth file into 3GP Converter telling it to use the right aspect ratio, but it still goes back to 320x240. How should I be doing it? Is this what you meant by config files in 3GP Converter?