I'm having some trouble properly setting up my subwoofer. I have it connected through the SUB out (LFE). There is considerable noise coming from the woofer even with the signal cable away from all power cords. The main issue I am having is getting my sub to play. It doesn't seem to receive a signal when the subwoofer is in ON mode. When I switch it to AUTO, it gets the signal, but there is a delay when the bass kicks in. When the bass dies down the sub cuts off. I adjusted the cross-over frequencies on the receiver, but this seemed to have no effect.  I'm not sure if this is a receiver problem or a sub probem. Thanks for the assistance.