I don't get it! I've used my PSR-630 for 5+ years and never had ANY problem with the accompaniment buttons. This membrane technology is nothing new. All our PC keyboards use it. I spilled coffee on my PC keyboard. I opened it, cleaned it off, and it worked again. The second time this happened it couldn't get it going so I got a new one. BUT, if I didn't dump coffee on it I'm sure I would not have had problems. I wonder if there is a dirt/dust issue here. Particles getting down where the membrane is can easily screw up the contacts. There really is no "switch" here with moving parts to wear out. It's just two sheets of plastic that having circuits printed on them. When you press a key it pushes them together at that spot (on the plastic "sandwich") and an electrical circuit is completed. Hmmmm....