I have owned this keyboard since day one and in the last several years, it has spent a lot of time in the repair shop. Right now, about 35% of the patches do not work. There is no apparent pattern for which patches will work or won't work. Many times if I select a patch thats doesn't work, and try to play a note, I will have to shut off the board in order to change out of the bad patch. Any one else have this problem or know whay may be causing it. I hate the idea of paying for my repairmans BMW!