Klipsch GMX 5.1 problem w/ Onboard Optical

[rrhomes]

I am not geting optical out of an MSI on board chip Realtek A97. I know that these are digital speakers and that unless I have a 5.1 DD ENCODER they wont do 5.1 DD, but I tought I could get stereo 2 channel out of my optical, and just the basic windows sounds. I had a SB Audigy 2 pl that would give me stereo out of the Digital Coax, but not 5.1. I know these are tricky speakers, but I thought since I got 2 channel stereo through my Digital SB Audigy 2 that I would get it with the Onboard Digital as well any body else know if I should be able to get 2 channel stereo out of the optical ot the basic windows sounds. I got them from my sound blaster so why can't I get them with the onboard. thanks david