Quote: My current boat was delivered with this problem, poor commissioning by a Spanish boatyard.
The connections were reversed, so it just tried to correct course changes in the wrong direction making the boat turn even more. A 6000, but could happen with a 4000 too.
Swapping the two wires sorted it easily enough.
This is what Raymarine have suggested ! New plotter etc just fitted last week, electricians coming back tomorrow afternoon so will report back on the outcome