I decided to take matters into my own hands on the Big Knob issue. Got in touch with the service department. The "jumping cursor" issue is a hardware issue with the encoder, and this is the part number for the replacement (Google it):
They are very cheap and very common parts. I ordered three of them, just to have some spare, and received them yesterday. The potentiometer/encoder is actually pretty small, it's just the plastic knob that is big
I will report back once I have replaced it in my Origin desktop. It's just a matter of un-soldering the old encoder and soldering in the new one. Most of the work will probably be opening the chassis and getting to the circuit board closest to the front panel that holds the encoder.