Asus Xonar D2 - buzzing/static

I have connected my Playstation 3 to an Asus Xonar D2 via digital optical cable. My sound card is connected to my Creative 5.1 Gigaworks speakers via analogue cables.

In the control panel, I've set the SPDIF recording option to monitoring and Validity Check is on.

When I try to play media/games with 5.1 on the PS3, all I get is buzzing/static noises. However, stereo audio is fine.

Any solutions?

This is because you're trying to send a Dolby Digital signal from your PS3 to the soundcard, when it only accepts stereo PCM input via S/PDIF. The Xonar is capable of outputting Dolby Digital (either from pre-encoded content such as DVDs or via DDL encoder), but can't accept it from external input.

I know someone on this board who also has a Xonar (D2X) and is able to play 5.1 audio from his PS3 just fine - though only Dolby Digital; not DTS.

Perhaps he's using different settings compared to yourself (passthrough?), or your optical cable isn't up to the job. Ask him.

I spent an hour talking to him, going through different possibilities. I have mine set up exactly the same as him. I've also tried both my £10 cable and a cable that came with sound card - but all optical cables should be the same as each other right?

Care to explain what passthrough is?

Optical cable quality does vary, some don't reflect the light as well as others which results in the signal being unreadable when higher bandwidth is required.

I can't really comment on passthrough as I haven't tried it myself, but it's an option I have on my onboard audio (Realtek ALC889A). Supposedly allows you to pass through the input to output.

This would work if he was using passthrough to send the PS3 signal to an external receiver (which decodes it - not the soundcard). IIRC the Xonar cards don't decode Dolby Digital in hardware - hence why they include the software version of PowerDVD in the retail package.

Hmm, I see

Btw, I noticed there are 3 slots at the top of the card, however there are no instructions in the manual that tell you to connect anything to them. Should I actually be connecting power to them?

Nope, those are internal audio connections.