Yamaha YPD V240 keys in octaves out of tune

by John
(Everett, PA US)

I have a YDP V240 and have say a key in each octave that is out of tune. I tried the standard rest of the piano based on web pages, and did not help. I have worked on these types of keyboards in the past and took apart the system and cleaned the circuit card and contact strip (was dirty but not the problem).

The standard reset I was told was hold down top key and turn on power but not really sure if it is resetting.

Can anyone help with this? I have a good ability to perform any work on this keyboard and others.