I have two nano-subs one sub works perfectly and the other has problems occasionally. Both subs are plugged into the same power source on the conditioned side of a panamax power conditioner. The are both in auto power mode. One sub works perfectly. With the stereo off one sub will sometimes kick on where you can easily hear a 60 cycle hum and faint voices from a radio station. It usually shuts off again in a few minutes. At very low volumes you can also hear the hum and interference. As soon as you turn the volume up to typical listening levels it's no longer noticable.

Is there something I can do about this or is the one sub defective and in need of repair?