Denford Software & Machines

Help please , i have an easimill 3 with a keb combivert 53 this has the 10k potentiometer connected center pin to ref outer to crf and the other outer to 0v. The problem is if you turn the speed up slowly it will sort of work but the slow down, it slows down at different places when turning the pot, the frequency counter on the combivert always goes up even though it slows down. I have tried a new better potentiometer and new wiring but it is no better,


Any help would be great thank you jasper