I had a look at the contacts today. The problem is the rubbers. I have bought some conductive paint to try. If this fails I will go for the replacement disk option. Today I did two coats which fixed half of them. The rest I have repainted right up to the sides. Hope it works.
I've notice another problem my effects pot seems to also act like a volume. I suspect the pot is faulty.
So good to be getting some sounds out of the keyboard!