Dave
Thanks for advice..It is not the sub must be receiver. I hooked sub to another system and it was fine..Even with receiver tturned off (Yamahaa HTR-5890) it hums rather loudly. Checked cords and replaced no help. It seems to be receiver related.. Any words of advice would be appreciated.

Mike

axiom m22ti vp100 q4s q8 rear ep350 yamaha 5890