Hoster with Vista and 2 Sound Cards?

[SteveD]

I am building a new system running Windows Vista and two sound cards. We have done this in the past using Windows XP with no problem. We selected the sound card for hoster as the default sound card and could tell windows Media Player to use the other sound card.

We do this so that our mixer can have one channel be for karaoke and the other channel for DJ music. You can run DJ music continuously and fade it in or out between karaoke songs. For some reason I have had no luck duplicating this in Windows Vista. Once I go into the control panel and make one sound card the default sound card, I can't go into Windows Media Player and force it to use the other sound card.

Any assistance on this would be greatly appreciated. Thanks,