I have a humming sound comming from my Sony STR DG820 receiver only in the 5.1 mode. Has anybody else experienced this problem? I used this amp on Polk Audio and Jamo speakers and it's there. I used the amp on my old Bose and it wasn't there at all, strange. The workshop said they didn't have a problem, but when I returned home with it, my speakers were humming away at low levels.
