Okay, I'm using an ASUS motherboard to output the S/PDIF signal to my Onkyo TX-SR607 receiver. When I go to the device in Windows 7 and do a DTS test I get sound from all 5 speakers, works great. The test for Dolby Digital the front 3 and the sub work, but the sounds for the two back speakers are channeled through the front left speaker.
I've gone through nearly all the settings on the Onkyo and updated the drivers
, but nothing has helped. As far as I can tell the Dolby Digital works fine coming from my playstation if that helps any.