How to stop audio sync drift on Sony AVC mp4's?

entilza72 wrote on 11/5/2010, 3:28 PM

Hi gang,

I have a specific need to create a high def MP4 with 5.1 surround out of Vegas 9. The "Sony AVC" MP4 codec appears to be the only capable codec out of the 3 MP4 offerings available.

Unfortunately, using this codec I find the audio slowly drifts in and out of sync by as much as perhaps 6 frames, every 20 seconds or so. (Of course, it might be the video that is drifting with the audio staying solid).

Has anyone else found this?

More specificially, does anyone have any suggestions for how to stop the sync drifting. I am hoping its something as simple as how often specific "frames" or "markers" are placed in the file, but there's actually very little in the settings for this codec.

Any suggestions?

Thanks,
Jason

Comments

farss wrote on 11/5/2010, 3:48 PM

"Any suggestions?"

No but I'm really glad you posted this. I now know I'm not going nuts.
Well, OK, I might still be going nuts however my ability to detect sync remains intact, phew.

Bob..

Steve Mann wrote on 11/5/2010, 3:49 PM

"Has anyone else found this?"

No.

What is your source media?

entilza72 wrote on 11/5/2010, 4:06 PM

Source media are cineform avi's, and wav files (high bitrate, hz) plus various generated media and psd's.

Project length may have someting to do with it: 15 minutes.

Cheers,
Jason