I've had my reciever for quite some time, has done the job well. It's a Sony STR-DE895 until just a couple days ago it was only used in stereo. Well I finally got my surround speakers and coax cable...so now I'm in Dolby Digital. Huge difference! But...one I don't know how to figure out and optimize all the settings....but I'm confused on why my screen will say "Dolby Digital 3/2.1" instead of something like "Dolby Digital 5.1" is there a difference?