Loud SNAP when AC3 Passthru icon appears - at DVD Start

gravymaker · Jan 8, 2005, 11:44 AM

Hi Guys,

I've searched all over to try to determine what is causing this - I could use some direction.

The situation:
I'm using Theatretek 2.06 to play DVDs. At the point when the KX ac3 passthu logo appears, I hear a loud, short "SNAP" from the speakers, but then the movie continues to play fine (and sounds excellent). Like momentary static, but VERY loud and it makes me cringe.

I've tried both the 5.10.0.3537 and 38g drivers, but the problem persists.

I am using a 2.5Ghz AMD and a Soundblaster Audigy2. I am passing the ac3 signal via spdif to my Bryston SP1.7 preprocessor, which feeds my 5.1 loudspeakers.

I didn't have this problem before with this exact setup - the only thing I can think of that I changed would be some of the ASIO settings (in winamp) and the KX ASIO panel. Since then, I've tried adjusting the ASIO settings but I'm really out of my league there - I'm not sure what is optimal for my setup, which is primarily PLAYING music and DVDs... no recording whatsoever.

Any thoughts? I really appreciate it.

Scott

**dj_stick** · Jan 8, 2005, 08:14 PM

ASIO won't have anything to do with this, imo it is to do with kX switching the stream over, and not exactly starting on the first bit, so the decoder things it is playing pure spdif for an instant, instead of ac-3

gravymaker · Jan 8, 2005, 09:35 PM

Ah I see - so I'm hearing un-decoded data for that half-second. That's exactly what it sounds like.

Thanks DJ, I appreciate that. I guess there's not much I can do?

**dj_stick** · Jan 9, 2005, 12:07 AM

not yet, i'll pass the onfo onto Eugene and see what he can do

hacker3000 · Jan 10, 2005, 11:37 AM

hi guys, i have the same problem, too. i'm using a audigy 2 zs connected to the creative decoder with a optical cable and then to the creative s750 (7.1). I solved this problem by muting AC97 (i think, i'm not sure coz atm i'm not using kX drivers

). when i switch back, i can be more precise... but test it with ac97. the problem is, i need ac97 coz i have a tv card...

**dj_stick** · Jan 10, 2005, 07:03 PM

mmm using only an optical cable?
then the only time you'll get 5.1/7.1 sound is when using pre-recorded ac3 content

sorry that was off-topic

eugene has been alerted to this, and has added it to his too do list

hacker3000 · Jan 11, 2005, 11:44 AM

Quote:

Originally Posted by dj_stick

mmm using only an optical cable?
then the only time you'll get 5.1/7.1 sound is when using pre-recorded ac3 content

sorry that was off-topic

eugene has been alerted to this, and has added it to his too do list

yeah i bought an s/pdif card and pinned it correctly to the AUD_EXT at the soundcard and it works fine

but the problem exist also with an coaxial cable...

sure, i mean dvd for example...

**Eugene Gavrilov** · Jan 11, 2005, 04:53 PM

yes, this is a known issue. will be solved later

E.

**dj_stick** · Jan 11, 2005, 05:05 PM

hacker3000: there is no difference between using an optical spdif or coaxial spdif signal

hacker3000 · Jan 11, 2005, 05:17 PM

Quote:

Originally Posted by dj_stick

hacker3000: there is no difference between using an optical spdif or coaxial spdif signal

i know i know, but you asked if this happens only with optical cable. ("mmm using only an optical cable?")

sorry... i don't speak good english and can't understand it very well

**dj_stick** · Jan 11, 2005, 05:27 PM

oh sorry, i should have said using only a single digital connection

hacker3000 · Jan 12, 2005, 11:20 AM

what do you mean with an single connection?

**dj_stick** · Jan 12, 2005, 06:37 PM

single cable

hacker3000 · Jan 12, 2005, 06:59 PM

i don't understand, can you use 2 ore more cables? but what's the reason to do that?

**dj_stick** · Jan 12, 2005, 07:40 PM

to get the extra 4 channels for 5.1 using standard s/pdif you need 3 connections

peate · Jan 13, 2005, 11:10 AM

Hmmm, I don't know. I used to use a DVD decoder card that had a spdif output that I would plug into my live drive's spdif input. I got perfect surround with both Creative's drivers back then, and with kX. I think since it's digital, they can put all discrete channels in the signal.

hacker3000 · Jan 13, 2005, 11:26 AM

Quote:

Originally Posted by dj_stick

to get the extra 4 channels for 5.1 using standard s/pdif you need 3 connections

very cool! but then you need also 3 decoders or not?

**dj_stick** · Jan 13, 2005, 04:24 PM

no, you just need a decoder that can accept 3 spdif inputs