Hi guys, I'm having a similar problem with my old Cambridge Soundworks P500 subwoofer. It gets power (blue light on), fuse looks good, bottom of case warms up, control module turns on with replacement power supply and turns green, though sometimes stays yellow when on "auto" setting. Marantz amp appears to be working fine, have monster sub cable from pre out to sub in on control module, phone cable works, tried with 3 different cables to be sure. Also tried different RCA cables to see if sub cable was bad. After all this, still no sound at all from P500 subwoofer. No hum, no buzz, nothing when I unplug one end and touch with my finger, nothing. Can anyone help please? One other thing, I did hook up various power supplies thinking they were the correct ones and this caused a red light to come on and a whirring noise in the control module. Maybe I fried the controller? Any help is welcome, including repair starting points. I can also connect directly to the amp using speaker wires, but I cannot find the old connector that came with sub to do this. Anyone know where I can source a new speaker wire connector for back of subwoofer? Thanks!