Ok, I have the sony DA5es which is a 6.1 system. I am using 5.1 speakers and was wondering if I had to disable the "sorround back" in setup, since I don't have the 6th speaker. When I leave it as the 6.1 and run the sound test configuration... I get a pause as it goes from the right sorround to the centre sorround(sorround back) to the left sorround. That is, the sound goes to that centre back speaker but is not audible since there is none. So, if I want to enjoy movies encoded in DTSes and Dolby EX, should I leave it as 6.1 or should I disable the sorround back in the receiver setup? Please give some advice on this as I would like to leave the system's setup in the best possible way. Also, could you recommend which speaker is best to use as a center rear(sorround back) Should it be the same as the sorrounds? or as the front centre speaker? Thanks very much for all responses.