edit: title doesn't really make sense but read on please... I've recently bought the HTS650 system from onkyo. but i can hardly hear the back channels when playing movies, xbox games, etc. it is suggested that I turn the volume of the backs to +8 and leave the fronts and woofer at 0? Or can this put wear and tear on my surrounds? thanks guy! and what is the optimal setting for this system using the 500 receiver from onkyo. thanks guys.