'Odd' frame rate causing audio sync problem ?? (XviD->DVD

[Mr Grumpy]

I have an XviD movie with 5.1 AC3 that has a frame rate of 29.972.

When I author the DVD I end up with a gradual desync of the audio (it starts OK and 'drifts' so that its behind the video towards the end).

I'm guessing that it's something to do with the frame rate - could it be?

This is what I've done

• extracted the audio from the XviD with VDub and left untouched

• Frameserved with Avisynth to CCE to produce MPEG2

• Authored the DVD with DVD Maestro

When in DVD Maestro it says the audio is just over a tenth of a second longer than the MPEG2. If this wasn't a 5.1 AC3 I would 'shorten' the audio with Goldwave, but don't fancy extracting the 6 channels to WAV, shortening them, then recreating an AC3 if there's a better way.

Will changing the frame rate (say in VDub or AVISynth) make any difference?

I noticed the 'Create audio sync' option in DVD Maestro, and while that created an AC3 of the same length as the audio, it hasn't corrected the sync problem.

Anyone got any suggestions or bright ideas?

TIA

Grumps.

[Gazorgan]

What is the exact framerate of the audio? This is a good example of why a PC will play anything. However, your DVD player will only play it at 29.97.

Soooooooooo, you need to squeeze the entire audio track by 00.002 fps over the whole length. BeSweet has the ability to do this correction for you with WAV, but not sure about AC3. Basically you are re-encoding the audio track at a slightly slower rate(it has a force 29.97 option). Then all you have to do is re-mux the new audio with the old encoded video and your done.

[Mr Grumpy]

I'm not sure how to tell what the frame rate of the AC3 is - is there a handy tool?

[Gazorgan]

Just load it in BeSweet. Also look at Headache. I can't look here at work :P but I've always been able to convert/fix between the 2 of them (and goldwave for those pesky DivX/AC3 to SVCD conversions)

[Mr Grumpy]

I've used Besweet to split the AC3 into 6 wavs, but as the movie is in 2 XviD files, I've got 12 to do

I'll use Goldwave to shorten them then join them back together with AC3Enc.

It just seems there should be a better way to slow down the video?