Hi Fritz,…did they fix the problem and how much was it? I have the exact same issue with back focus adjustment only working for each ND and then needing adjustment when changed to another.
I had rented my camera out and the operator confirmed that he or one of his shooters used the zoom ring when the servo was engaged and I believe this is what caused the internal lens issues. I need to send mine off to repair because I don’t think I can fix it through firmware or other self help methods. Sucks but learned my lesson on who I will rent gear out to!! I have insurance but didn’t want to claim unless I have to.
Tony