I have installed two new radios, VHF and FM. Both radios have a low grade hum when the Adler-Barber kicks on. In fact you could hear the hum in the speakers even if the radio was not on with the old FM. The fridge is on a different bus bar than the radios but it would seem to me the hum is coming from the compressor and feeding through the 12V side. Does anyone know if there is an RF filter available?