I think Radio Shack has a 6 channel switching box - so you could have two multichannel inputs into the switching box with the option of choosing between 2 multichannel sources, then a single set of multichannel outputs from the selector box into the ICBM.

I used to use a receiver as a processor, now I use a dedicated processor.

Enjoy the Music. Trust your ears. Laugh at Folks Who Claim to Know it All.