Check continuity between Pin 21 of the processor socket and Pin14 of CN12 on KLM371. Actually you should have continuity between this pin and one side of all the button switches (but not the slide switches).
Message
[PolySix] Re: Apreggio, Chord Mode, Unison, Poly button do not work. Help?
2016-04-30 by Malte Rogacki