The center switch in the hydro lever has been known to act up_stick or quit working. From your description of the problem that is what I would look at first. There has been an update recently to the four way version of the switch to solve this issue.
I got this fixed at the dealer today, it was the coil at the header lift spool, why it lifted a greater distance with a bad coil than a good one I can't understand. Torque