Currently working on a Polaris that was severely mistreated.
Replaced the membrane panels, several pots; upgraded the ROMs; tuned &
scaled the power supply, DAC, CPU and voice board per the service manual.

Two voices (3 and 5) will not pass tune. Re-enabling them shows that
Oscillator B on both voices scales sharp towards the upper part of the
keyboard; also, when playing the filter resonance from the keyboard,
those two voices are out of tune with the rest.

What I've done so far: swapped out ALL ICs on the two offending voices
-- no change.
Swapped out all the sample/hold caps and oscillator timing caps on the
two offending voices -- no change.
Replaced the four ICs (Z60 - 63) in the sample/hold control circuit --
no change.

At this point, I'm out of ideas as to why these two voices are behaving
this way.
All memory functions, internal and external controls, and other synth
features are working correctly on all voices.

Any suggestions?
Thanks.
~GMM