[WT]

Get one of the PAC units it cure the problem. It just seems there a ground loop that gets created when you plug in a source into the 3.5mm AUX jack and that same source is gettign power for 12V in the truck. I used the PAC SNI-1/3.5 and it cured my problem with AUX input from my Blackberry to the the AUX port to stream digital radio to it. Cheap and quick fix. Ypu you want to test it out get a secondary power soruce to feed the input device battery or maybe ever 12V from a battery charger you see that the humm goes away when there is silence or simply pull the plug from the AUX jack no more humm cause your introducing it through the source device when plugged in.