"Wall Wart" hum, unavoidable?

I just got off the phone with Larry @ MD. The hum is coming
from the external wall wart, not from the receiver or through the speakers. Larry is sending me a new wall wart
which he said will solve the problem. However, he added that the new MD 102 has an internal receiver thereby reducing rack clutter. Unfortunately, it is not possible to
upgrade my unit. Thanks for response.

I just spoke to the factory about your hum problem.
They did have a bad batch of wall warts that over time,where the winding inside the wart(transformer) would loosen and starts to hum. The warmer it gets.....the hum gets louder.
They recommend to send the remote unit back to them so they can rectify the problem and in the mean time put the 7 pin din plug back into the socket on the rear of the tuner. If you lost the plug, they will send one to you.
Ask for Larry or Vince at Magnum Dynalab .
Tel#905-791-5888
I hope this will help you out
Best regards
Larry/Hollywood Sound

The best thing to do would be to unplug the remote receiver and tune manually. How often are you really going to need to change stations anyway?