CEM 3340 VCO Question

[R.Fahl]

I'm having a problem with one of my 3340 based VCOs.  The Coarse tune pot
barely affects its frequency for almost the first half turn, then goes
through the entire audio range in the next quarter turn.  I've tried
adjusting the V/oct trim and the hi frequency trim with no positive
results.  I have two other VCOs of the same design (Tom Henry's Deluxe VCO)
and they don't have this problem.  Do any of you have any pointers as to
what the problem might be?

Romeo