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I've got this problem with my SPDIF audio occasionally skipping. The video is excellent but the audio will skip just for a second every so often. The interval between audio skips seems entirely randomly from as little as 5 seconds to as long as a minute or two. Upon the replaying of a given scene, the skips will occur at different places in the scene. This is NOT a problem when using analog out...only when I use digital out. My sound card is an Audigy. Which DVD player I use doesn't even seem to matter ... ATI, CinePlayer (both are Ravisent) or PowerDVD ... they all audio skip exactly the same way. CPU is never overloaded (uses >20% of CPU time with hardware acceleration and ~50% without ...I 've been monitoring it with the Windows Task Manager). Plenty of memory is available, no IRQ conflict according to the Device Manager (and I even went so far as to change the IRQ several times just to make sure) ... I have DMA enabled on the DVD drive. Is anyone familiar with this problem? I've search previous threads but there were no definitive answers/solutions other than purchasing more hardware (ie. buy a different audio card). However I feel sure there is either a software solution to this problem or a simple work-around. Any suggestions would be greatly appreciated. Anyone think a digital cable going from the DVD drive to the Audigy sound card would by-pass the "obstruction"??? ... or would I wasting my time trying this??? Please, if you know anything about digital sound, offer me some direction I'd be entirely grateful. (If you've ever experienced the same problem, your moral support would at least make me feel better.) Thanks to any and all who may respond.
 

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I had exactly that problem. Was using the wife's PC which happened to be in the same area as the home theatre stuff (basement):

PIII 733MHz

i815 chipset mobo (pulled from an HP Vecton - got it cheap)

512Meg PC133

GF2 GTS

Asus 8xDVD Drive

SB Audigy OEM

S/PDIF cable from Audigy to Yamaha Receiver

PowerDVD 4.0 XP

Windows XP Pro


The sound would cut out for a split second every 30 secs or so. Also, selecting DTS sound with a DTS movie would turn the video to a slide show.


So later, I put the Audigy into my PC and tried again:

PIII 1 Gig

Asus CUSL-2C

512Meg PC133

GF3 Ti200

Asus 8xDVD Drive

SB Audigy OEM

S/PDIF cable from Audigy to Yamaha Receiver

PowerDVD 4.0 XP

Windows XP Pro


...and the sound is now perfect. No cutting out. Even when DTS sound is selected. Picture on the NEC 6PG is awesome too.


So what was the problem? Don't know for sure. Could be that the PIII/GF2 GTS wasn't up to it. The Vectra MoBo had onboard sound that was still enabled, so that might have been it.


Only problem now, my PC has now become the home theatre PC and I can't play games - waaaaaaaaah!
 

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I've got the same problem on my HTPC. I'm using a SBLive with WinDVD or ZoomPlayer (using the WinDVD audio filter), and get a 1 second dropout at random intervals.


I'll be changing my DVD drive soon, maybe that will make a difference...


I think the digital out on your drive only carries PCM; it doesn't route AC-3 or DTS off of a DVD.



Win98SE

Athlon 1Ghz TB

MSI MB w/Via KT133 chipset (with Sound Blaster patch)
 

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I wish I could help too... but I can't. Can only say that my previous system did this... Audigy/Hoontech on a AMD760MP board. I got different results by moving the Audigy board around to different PCI slots. Eventually I got fed up and moved to a P4 based system with on board c-media s/pdif out and it works just fine. Wish I could help more.


-rick
 

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I had the same problem with my setup


SBLive value

Radeon VE

Cel 450

128Mb


But I fixed it after doing the following, I don't know what fixed it but I suspect part 2)


1) Changed PCI slots...


2) I noticed that there was a large potential difference between the ground on the computer & the ground on the SP/DIF cable from the amplifier. So I put and RCA socket on my computers case (grounded to the case) and passed the digital out through the RCA socket by connecting the correct pinout on the AUD_EXT header on the SBLive! See the attached image.. You want pin #17 going to the centre conductor of the RCA socket & pin #18 going to the ground of the RCA socket (and hence also computer ground as the socket itself is grounded on the computer case).


This will reduce the amount of current flowing directly through the soundcard (caused by the large potential difference) by using the whole case as a ground.


I cannot guarantee the AUD_EXT connector is the same on the Audigy but it is likely. You should look it up.


Hey, it worked for me! Hopefully it will work for you if you choose to do this as well.


Regards

Cam
 

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I think that CameronR hit upon the real problem, being a groundloop between your PC and your receiver. Good equipment has an isolation transformer both at the SPDIF input and output. Unfortunately the PC SPDIF doesn't. Better grounding may work or you could go to optical and get rid of grounding problems altogether.
 

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I had the same problem. It was a ground loop issue as CameronR suggested. My solution was to switch from using coax to optical for the SPDIF connection. Optical cable is electrically inert and thus avoids the problem. If you have optical connections on the Audigy and your receiver then this might be your best (and cheapest) solution. Otherwise you can pick ground loop isolators from RadioShack for your coax connection (haven't personally looked for or used these myself but I remember someone suggesting them as a solution from a previous forum thread).


Cheers

Lester
 
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