Mach 460 Problem

I have a problem with my Mach 460 sound in my 1994 Mustang. Lately it has been acting up with things like taking 2 or 3 presses for the deck to come on (the top one with the radio and cassette player). It also sometimes would regardless of the last station I was listening to revert to the default 640 station (like what happens when you disconnect the power at the battery). Today it displayed the error "BAD0" on the display, so I turned the car off and then back on. It now says simply "BAD" on the display. Does anyone have any idea as to what this means? or as to where my problem lies? Any help is greatly appreciated!!