Thanks for the suggestions. I've been thinking about the Asus Xonar as my Win7 PC is right next to my xbox360 but that would most likely interfere with it being an entertainment PC with Netflix being watched constantly all day. Will the Xonar optical in and out while not being default sound option for the PC for it to be used xBox --> Xonar --> E17 while on-board is set to default to hear computer audio??
Did not know of any internal Xonar sound card with an optical input?
Any sound card that has an optical input (Titanium non-HD) is usually only 2-channel.