Hi BRC,

Try coiling some of the cables from the sub to the PC into a coil and rotating the coil. Use a twist-tie to keep the shape. You may be able to "tune" out the offending TV interference by moving the coil around. Use a coil or a figure-8 when you coil up the cables. You're trying to "null" out the offending signal. Are you near a TV transmitter?

Regards,

Alan Lofft,
Axiom Resident Expert (Retired)