Vintage Synth Repair

Dear Randy [and list ]
the Oberheim OB-8 uses the cem 3340 oscilator ic.
its possible that that might be the fault , but it could be something
else .
if the ic's are in sockets you could try carefully swapping the ic with
a known good one [ always turn power off and pull out the mains plug
when you try to swap parts ! ].
it should be possible to work out which voice ic is the one that is
misbehaving from the service info .
data on the cem 3340 and other ic's can be found at 
http://www.synthtech.com
regards Peter