yeah its not blown....
when we put the dvd player in my car, only way we could run the headunit and dvd player was to hook the accessories power wire to a switch, so we could flick between either headunit or dvd player, and it used to reset the clock and headunit, which in turn gave me the shits after awhile. so now i just have the headunit hooked up and it doesnt do it anymore.
its something to do with the accessories power wire... it isnt blown, its just the way you've got it connected i'd say.