AC3 Audio drift

[crose]

I've been backing up a number of my DVD's to AVI to have online in a HTPC. I use the latest DVD Decrypter in IFO mode to rip the DVD's before using AutoGK. Within AutoGK I choose AC3 audio, 80% quality and generally no subtitles.

I'm experiencing audio sync drift over time. When I start the AVI, no matter where I start, the audio appears in sync, then over about 20-40 minutes it slowly goes noticeably out of sync. If I stop and start again, I'm in sync again, however I keep having to restart the video.

The fact that the video is in sync to begin with tells me that, most likely, the AVI file is fine and it's my player, codecs, audio driver, etc. that is to blame.

I'm using an Audigy Gamer card with SPDIF out to a digital pre-amp -- updated the Audigy to the latest drivers. This is on a 2.53Ghz P4 system with 512MB of memory running Windows XP. The video card is an ATI 9700, FWIW.

I'm using AC3Filter v0.70b and XVID codec 1.02-29082004. I've tried playing the AVI under Windows Media Player 9 and 10 as well as BSPlayer. I use WinDVD6 as a DVD player and BSPlayer showed the Intervideo AC3 audio codec being used while Windows Media Player showed AC3Filter being used -- not sure the implications of this.

Any thoughts on this frustrating situation would certainly be appreciated. Many thanks to Len0x for a great tool...

Charles

[musicnyman]

i had the same problem in the divx codec but xvid worked fine.

you using divx or xvid? if divx, try xvid... i like xvid personally better than divx, no problems and have converted 50 dvds so far, including ac3 audio.

[crose]

I'm using xvid...

As an update, I upgraded the audio card from an old Audigy to an Audigy 2 and updated to the latest drivers from the Creative site...this seems to have fixed the problem. I was reading that some old audio cards don't have internal clocks that are as reliable as the new models. So far, this theory seems to be right.

Thanks for your reply,

Charles