I bought a cd player for my car that says it is blootooth ready, mp3 ready, compatable with mp3 players, xm radio ready ect. It does not have a a port for usb cable, the little square port, but it does have a round jack port like what you hook head phones up to. Could that be a way to hook up an mp3 player? I mean is there another cord for that. A friend of mine has a cd player and they use their mp3 player but not with the usb cord. I'm knew to the mp3 player thing these kids use, but they are a lot better than hauling 50 cds in your car that could get ruined or stolen. thanks so much!