So I've had an issue where fader #2 is "sticking" - motor keeps trying to ram it down to inf. I scoped the board, and determined signal going up to drive portion was good.. Tested transistors and they tested OK, but I replaced the NPN's anyways. Finally today I got to testing the diodes, and sure enough one of the zeners tested out shorted. Too late for parts tonight but first thing tomorrow I'm off to get a replacement.
Here's hoping!
Sid.