The subwoofer (a self powered Bag End Infrasub 18) now has a noticeable hum. Not sure if the hum existed before, because I recently re-arranged the furniture.

As a test, I moved the cable from the 950 to the subwoofer so it would not be near any other speaker or power cables. But this did not eliminate the hum.

Any thoughts on how to eliminate the hum? Thanks for any help.