Problem with speakers or deck?

[exmonkeypunk]

My old nasty cheap tape deck finally quit getting power, so i found another Sony tape deck in the garage and wired it up... Problem i'm having is if i shut the radio or vehicle off, there's no sound. I have to un twist then re attach the speaker wires every time i turn it on to get sound. Does this sound like a ground problem with the speakers? or maybe something with the deck?