Hi. I've got a subwoofer that hums, very noticably so when the amp is turned onto standby mode. It's a decent sub (Castle) and from reading other threads the possible solutions are 1) buy better cable with good shielding, 2) by some sort of humming prevention device, 3) mess about sticking earth leads into the mains. 1) Can anyone recommend a good cable with a single phono plug on each end, and tell me where I should get one from? It would need to be quite long to go from one end of the room to the other. 2) Alternatvely, sme question for a hum removing device. Thanks.