Noise or HUM from BFD

[rkruz]

I am getting a humm or noise from the subwoofer with no inputs.
This noise occurs with or without a subwoofer input to the BFD.
The noise does not occur when I switch to another preset with factory defaults.
I have 7 filters in the 20 to 100 Hz band. Seems like it occurs with even 1 filter active.
I have turned off all filters and the noise goes away.
I have tried different cables including RCA and balanced with no change.
Both units are plugged into the same power outlet.
Sounds like processing noise is being output.
Is this a common problem? It would make the BFE unusable for me in my Home Theater.
Maybe I have too many filters running.

Any hints to try to improve the hum would be appreciated.

thanks again~!
.

[brucek]

Doesn't sound like a ground loop, but to be sure you could use an AC cheater plug as a test.
If it is eliminated with the cheater, then there are safe solutions.
If the cheater doesn't work, then you have a faulty unit.

They generally make no perceivable noise at the sub frequency range..

brucek