I've been using sony MHC gnv99d for a couple of years now. in the starting, everything was working fine, but soon enough problems started arising at first the head of the DVD player got corrupt and I had to get it replaced at the sony service centre. then the cassette player stopped working. I had to get that repaired again. Then eventually the panel buttons started creating problems, there was a mismatch in commands given to the system. touching one button would give some random another command to the system. I got this repaired at the sony service centre. And now, now these buttons have totally stopped working including the on/off button. how many time do I have to get this repaired?!!! why are these buttons not working now.?