Vintage Synth Repair

Hi guys and first of all happy easter!!!

I have some free time finally so decided to check OB8 ...
It had few problems but ... 

found dead TL081, CA3080 ... kinda regular problems that i fixed easy by replacing ics

Next is 2 voices that wont go in tune!!

so Voice 6 //// VCO 2 is going crazy //// tried with another CEM 3340 ... same thing

VCO 1 and VCO 2 are getting same KEYCV.. VCO 1 track perfect ... VCO 2 is kinda playing what he wants !!
.. so .. voltages on VCO 2 are ok ... +/-5 and +/-15
IC 3340 is fully functional one

KEYCV is from same source to VCO 1 and VCO 2...

Any idea???

Thanx

Damir