Well... Still no luck... I've unplugged all my devices and still have the hum. I plugged the AC to the same strip with no luck. I figured my Marshall was interfering, so I re-routed the audio cord which helped reduce the hum; although quieter, it still exists. I I think I need a heavier insulated audio cord. While plugging and unplugging (I wish I could plug something else); I disconnected the audio cord from the receiver, the hum still existed.
I'm too sick to mess with it anymore... I'll try replacing the audio cord later.
Thanks for the suggestions.