I have about 1500 hours on ours, and I do not suffer your problem.
Can I suggest we discuss via face time, I will send you details by PM.
When we work out your issues then come back and post the results here for the benefit of others.
But in short, Sensitivity and gain values are the likely problem. Perhaps your speed control. Maybe mechanical linkage stuff.
It will work fine you just need to get the bug squashed!
DYNON Authorised Dealer and Installer
The two best investments you can make, by any financial test, an EMS and APS!