I've just installed an Asus D2X sound card in my Win7Pro64 system, which has an i5 processor and MSI motherboard. This card replaced an earlier card (different brand) that had the same problem. The motherboard audio is disabled through the BIOS.

I don't want 'manufactured' DTS sound, I just want to be able to play my FLAC-encoded DTS and stereo tracks through my external surround receiver, which has DTS and DD decoding built in. The receiver's digital input is connected to the D2X with a coax cable from the board's S/PDIF output.

I've tried every combination of Windows' 'Sound' settings ('Speakers', and 'S/PDIF pass-through' from D2X), with every combination of the D2X Audio Center settings, but all I can get is stereo music (sometimes!).

In Windows' Control Panel 'Sound' app, I can select DTS pass-through, and when I do the tests for DTS it plays correctly (all speakers, in turn) through my receiver, showing 'DTS' on the receiver's display. But if I select S/PDIF: PCM in the D2X Audio Center (all volumes set to 100%; no effects or DSP), I can only play stereo tracks (though even they don't always come through the receiver!). When a DTS track is played (I use WinAmp), the receiver remains silent and does not show the DTS icon in its display. [Incidentally, this same setup (external receiver and WinAmp) played DTS correctly in my previous Win2k PC with a different sound card.] I've tried several different player programs, but all give the same result.

If I then select 'Speakers' in Windows Sound setting, leaving everything else as before in the D2X Audio Center, the stereo tracks play too loud, and now DTS tracks play as white noise (which means the DTS stream is at least now reaching the receiver, but is corrupted).

I'm new to this forum, so I don't know if this question is too technical for the members here, but I believe this is a Windows 7 problem rather than a hardware problem. A similar setup worked fine under Win2k, and other forums indicate many people are having this problem with Win7. I hope somebody can help me get DTS pass-through working from the D2X (as well as stereo through the same S/PDIF connection, of course)!

Thanks. Daniel