1990 ZR1 with delco bose stock cd player sereo system. Its my dads ZR1,its got 3,300 original miles on it. The stereo wouldnt work when we first got it back in august. We replaced a copule things to maki it all work again, i forgot waht we replaced (something in the passenger side dash and 2 rear speakers along with the amps) It was a total of $800 and everything worked perfect after that. Well it sat in the garage over the winter with the battery out of the vette. We started it back up today and he went to play music........There is a constant HUM coming out of only 1 speaker

just the driver side rear speaker. It goes from high to low pitch and just hums. The stereo wont play cds or radio :!:
we are stumped.

whats up with this stereo?
thanks
Walter