Navpilot 511 knob malfunction



Anyone have experience with a malfunctioning control knob on a navpilot 511 display unit?
When I try to adjust course in auto mode, it jumps around...sometimes jumping 10 or 15 degrees and sometimes not moving at all and sometimes actually jumping backwards (turns to starboard when I turn knob to port) etc.
I have a remote unit in the stern that responds perfectly and precisely, so I am 99 percent sure it is not the processor. It seems to only be a problem with the knob on this display unit.
Furuno says it will cost at least 700 to 1000 to repair. A new one costs around 700 so I am thinking of just buying new.
I could just adjust course in manual mode and then hit auto but I am worried this problem will get worse and the unit might die completely at the worst time.
Anyone have this issue and found some other fix besides buying new/sending in for repair?
Can you get just the knob and replace?

Thanks for any advice!

I would suggest sending the control head into our Camas, Washington service department.
If it is just the rotary encoder it can be repaired with a $30 part and approximately 1 hour or so of labor.

We also still have 511 control heads available. Without the cable it would list for $745. (I'm sure you can find it with some discount)
If you decide to go the route of replacement it is very important that the software of your system matches. Provide whatever supplier you might use with your current control head software version so it can be loaded by Furuno before we ship it.