Don't know about x36 pots myself, but if they can be dissasembled then you can wipe the surface of the pot clean and apply a very thin layer of vasaline.
This works great on TM gear.
Maybe some one has the URL for cowboys TM web site, I think they have pitures of this procedure.
I did it to my TM joystick and the spiking went compleatley.
Grayarea.