I have a Sony DAV-SC5 compact AV system. The system freezes when I put a DVD disc on. The remote and the buttons on the console do not work. I have to turn the system off then on the eject the disc. The screen freezes on the opening chapter display and I can get no further. If I insert a disc with no opening credits, the system plays OK but again I cannot pause, stop skip etc. To stop the play I have to turn the system off then on to eject. The system is just out of warrenty. Are there any firmware updates?