Hey, I have an X-fi Xtreme Music card & Klipsch Ultra 5.1's. I have CMS-3D on, on Stereo Surround.
My problem is that when I play music it seems like its just being thrown at me from the center speaker with some sub in there. My left and right front & back speakers don't seem to be nearly as audible. I don't like it like that at all If I turn on Stereo Xpand, the problem is 10 fold worse.
Can't I just get it to treat the left front & back speakers as the left channel, and the same for the right, with bass handled by the sub? Ehhh. I don't know, I think that's how my old card (SBLive! Xgamer) handled it on my old speakers (some crappy Altec Lansing 4.1).