1 mega-ohm still not enough! Though much better. May do a voltage divider before pot.
Also, can't get CV mixer to work, so will either build MFOS mixer (which I have for audio out from mono 1 and VCF2 (as separate filter input) OR I may just get an RC4580, as this op-amp operates at 5V no problem. Getting some fat sounds out of it so far - will put some demos up soon.