[Wayne A. Pflughaupt]

aspeters wrote:

Is it possible/appropriate to use connect any/all of the receiver, sub, or BFD with "balanced" cables instead, and eliminate hum?

What brucek said. To embellish a bit, a balanced signal path requires each component to have balanced outputs and/or inputs. At any point where you insert an unbalanced component into the signal path, the signal path then becomes unbalanced.

Regards,
Wayne