You know, Gonk, sometimes the most obvious thing staring me in the face I miss. When I set the Surr speakers to "None" the menu wouldn't allow me to set the Surr Back to anything other than "None." It never occurred to me that the setup was as you said.
OTOH, the manual never reads, "To set 5.1, do the following...."
Watch out. Dumb question #3 is brewing!

Jay