I'm trying to setup multiple soundcards in my HomeSeer Server which is running WHS so that I can have different audio zones through the house.
The server has a onboard soundcard which works fine and I can plug in any of my audio zone amps into this card and the amps and speakers all work perfectly. However I have also purchased a couple of USB 3D Sound Cards (USB 2.0 TO 3D AUDIO SOUND CARD ADAPTER VIRTUAL 5.1 ch) to use as other sound cards for other zones, these work fine and sound great when I plug a set of headphones into it. However when I plug one of my zone amps into it the music is all distorted. I've tried lowering the output volume and its still distorted, if I unplug the amp and plug the headphones in again the sound quality is perfect.
My 1st assumption is you have a conflict trying to run onboard and external sound. You will probably have to choose either or.
Disable onboard and add your sound cards. I have never used more than one sound card but I supose that if you have the correct drivers installed for each card it might work. Im not sure of that but I do know onboard or external is a choice of either or, not both.
It might help if all cards are the same. Thats an interesting project. Update us on how it turns out...