EBTECH's Hum Eliminator products use their custom Isolation Transformers to break loop antenna that causes ground hum and buzz. The Ebtech Hum Eliminator also converts back and forth between balanced and unbalanced connections and prevents the cable from acting as an antenna for noise. Simply place a channel of the Ebtech Hum Eliminator on the cable connections between the two offending pieces of equipment. Will not affect the quality of the audio, it will improve it.
EBTECH uses 1/4" smart jacks that accept any combination of unbalanced (TS) or balanced (TRS) plugs. These are passive devices (no power required), in cold rolled steel housings, hand-soldered circuit boards and top quality components and hardware.