I've got a 605, but I'm assuming it's essentially the same. Also, it's much easier if you read the manual than if I try to explain how to do it. Look up "listening modes" in your manual.
Basically, this is how it works: for each connection to your AVR, you'll have a variety of different possible audio signals being sent to your AVR through that one connection. Each of those audio signals can have (but doesn't need) its own listening mode. By setting the listening mode for each signal type for that connection, you're telling your AVR how to deal automatically with each audio signal it gets so that you don't have to change it manually each time.