Discussion about the Korg PolySix synthesizer

Hello all;

I bought a polysix in rather bad condition...

I did the batteryreplacements and checked to circuits...they seem to
be OK for both sides of teh PCB 
...many things were still wrong then I replaced the IC31...and the octave 
knob and the sub osc were working again.

The Controls are better now but still don't work correctly..

the MG....Delay doesn't work at all and Level gets controlled by the
VCO PW/PWM knob...? the EG doesn't seem to work either..
only the sustain can be controlled via the LFO resonance knob..

all the other things like the preset section / loading saving progamms
or even sending and receiving banks form external casset recorder
works....!!!!!

when i try to do the testing procedure with the 56k resistor...the 
following happens.....when i turn the trim clockwise there is a point 
where is jumps from bankA prog1 to all eight proglights.....this doesn't 
happen 
for me the two first ( prog 1+2) don' light...sometimes 
its only the first one which doesn't light...
when i remove the resistor it switches back to prog1 bankA

I have no idea what could be wrong...could it be IC30 or even the 
processor ?? Did you have something simlar ? 

How much would a new proc cost?

I really would aprichiate it a lot if you could give me some advice...


thanks in advance

Gregor