Technics SX-PX73M Digital Piano Repair

by Peter
(New Zealand)

Technics SX-PX73M Digital Piano repair problem!

A fault has developed in my Technics piano where some notes play very loud, not in keeping with the other notes. In my case it is D sharp, F and A.

I think a power surge may have induced the fault.

Has anybody else had this problem?

Any idea how it can be fixed on my Technics SX-PX73M Digital Piano?