My , JVC RV-B550 portable cd-player does not respond in my (original) remote control. I' ve replace the old batteries with new one, but nothing. I have no idea where is the problem. In my cd-player sensor or in the remote control? Is there any way, to found which one of the two above, has the problem? I don't want to buy a new remote-control without to be sure that it is the problem.