Just set up my parents new plasma and noticed there isn't any sound coming from the rear speakers in their HT. I ran Avia 5.1 speaker identificaton to confirm. I can barely hear the test phrases ("right surround" then "left surround" through the subwoofer). I also switched the wires and verified that the speakers do work (sent the center channel signal to each rear to test). The Sony 333ES's display shows all five speakers. It is set to AFD and the blue light is on. I am at my wits end! Can anyone think of what I might be missing???