Crossfader in the OT are fantastic!!
Very similar or exactly the same used in Rane ttm56
http://www.rane.com/ttm56.html#gpm1_1Please correct me if I am wrong.At one point I had some bleed problems with one of my
faders on the
ttm56 but it was easily corrected by
adjusting the magnetic sensor on the relevant side
of the fader internally.
They can take alot of punishment in fact I think
the fader is so under used in the OT (dynamically rhythmically).
Rane use to have a sewing machine permantly attached
to the crossfader on their website constantly pumping
the crossfader hundreds of times per minute to demonstrate
how durable they were.
DL the service manuals for the mixer for some servicing tips.