Ditto to Gary's remarks. I've had PSR70, 6100, 510, 630, 740, 8000, 9000, 2000 and now 2100. I may have left out a couple. All were played a LOT, and in all sorts of conditions. The 2000 was used for more than two years, average 5 jobs a week.
It's now still performing out in California, with no faults as far as I know.
For that matter I've never had real problems with any keyboards except the Roland G800. The spring in the joystick broke shortly after I got in. And within a few months, a lot of the buttons were loose and hard to work, and the paint was worn off in several places. Maybe it was a lemon, but it put me off Roland.
Anyway, good luck with your repairs. I know others have had problems with the variation and fill-in buttons on the 2K.
DonM