I have the D2 that I just installed in a Mercedes E430. It sounds fine when the ignition is turned to the first setting which I think is acc but then if I turn the ignition to the second position, before starting the ignition, I get this high pitched whine. It does not seem like alternator noise because the intensity doesn't increase when I start the engine or increase the RPMs. The noise doesn't increase if I change the volume on the avic but does if I change the gain on the amp. Also, I've already checked all the grounds and tried grounding the RCA shields to the chassis and or the avic body
