Hum in Subwoofer with trouble shooting issues

I have a Mirage BPS-S210 with a LFX-3 Crossover. I recently lost power to the room (house) from a storm and now I have a hum in the sub that I seem to can't get rid of. I do not think the sub is damamged because I have a LOT of protection (Monster AVS 2000, HTS 5100, HTS 2600, AP200, Protection in each of the Circuit Boxes as well as high end breakers) I have been swapping out the cables and I put the cables on the other sub (HSU VTF3 MK3) and I do not hear the hum, but when I return the cable to the BPS-S210 I hear the hum again. I have bypassed the crossover, still hum's. How do you "drain" a line. I have heard a couple of installers use this term. I am really looking for answers.
To drain the line, just unscrew the RCA plug on the interconnect that attaches to the sub, and pour the electrons out into a cup. Then you teach them the words so they don't have to hum ;~)

But seriously now... You've eliminated the IC as a cause of the problem. If there is another sub on the same system and it does not hum, but is connected in the same way (make sure AC power is same),then its likely that the sub is the problem. Try putting the IC from the good sub on the humming one and if it still hums, then its even more likely that its the sub. Can you swap it into another system?