The AC3 audio goes "ping..pong"

[cornetet]

I'm a Newbie...

I have tried to demux several 6ch English audio tracks from different DVD's now thru DVD2AVI inside GKNOT.

To test things, after the demux, I've been playing the .AC3 audio back BY ITSELF and just listening to the audio... to make sure everything is OK.

In addition to the Movie Audio Track, my .AC3 files are playing strange audio patterns... One demux I did produced a "ping-ponging" sound. Strangely enough it sounded like a Metronome. On another demux the audio track played back very choppy.... a very distinct pattern of 'skips'.

ARE THESE STRANGE AUDIO PATTERNS SUPPOSE TO BE THERE WHEN ALL THE
.VOB'S (that make up the movie) IS DEMUXED INTO A SINGLE .AC3 FILE???

[wasbeer666]

From my personal experience I can tell you that a movie with Ac3 track is quite demanding. Par example, I encoded terminator 2 6ch with ac3 track (through Besweet and muxed via virtualdub) and the playback was very stuttering with video catching up al the time.

The system monitor said cpu usage of 100% continiously on my PIII 800, 256 mb 133 ram and a ati 128 pro 32 mb graphic card.

Just my 2 penny's:p

With kind regards,
Guido

[MaTTeR]

Playback isn't so demanding if the AC3 is muxed correctly. AFAIK Nandub nor Vdub really do a proper job with it.

I'd suggest muxing the AC3 with AVIMuxGUI using default settings and then see how demanding playback is;)

[cornetet]

I appreciate everyone's input, but the question still remains:

When you demux an .ac3 audio track and just play it by itself (to test things) are strange audio patterns suppose to be in the track?

I just want to know if the .AC3 file I've got with sound patterns in it, is CRAP or not.....

[MaTTeR]

Oh my...just noticed you were located in Bearcat country;)

No you shouldn't hear any strange effects when playing back the AC3 using Zoom Player, BSPlayer or PowerDivX. It will sounds just like you'd expect during normal DVD playback. Are you using Direct Sound or Wave Out? Which AC3 filter do you have installed?

[cornetet]

...not sure. the only audio-related program I've downloaded is 'AUDIOFILTERS' and loaded it for win2k

[UGAthecat]

Try loading the demuxed ac3 in powerdvd and playing there. I have the same problem right now, in that using windows media player, or anything other than a native DVD player doesn't play the ac3 audio correctly, but powerdvd does.
I am getting the same noises that you get, and it happens no matter if i have the ac3 decode on the PC or on my receiver. I'm guessing it has something to do with a few of the issues mentioned in matter's ac3 guide but haven't had time to try the proposed fix(something about needing to wipe out all ac3 decoders and start from scratch).