Since this problem seems to occur only with original rolls, let's
start there.  If a roll is unevenly wound, tightened and stored in
a hot attic or damp basement, the paper will be effectively "trained"
to wander back and forth when played.  You tap the paper down against
the right (slotted) flange when loosely wound, and it will misalign
again even with the slightest tightening.  And once a metal-flanged
roll is dropped onto a hard floor, damage to a flange may be concealed
and/or permanent.  Check both flanges for wobble during rewind and deal
with it as best you can.

The earliest Duo-Art players have holes in the tracker bar for tracking
with no screens to trap lint and dust which would quickly clog the
pathway to pouches and bleeds.  If your tracker bar has these "extra"
holes, the ear assemblies were probably added later, sometimes even
before the piano left the factory.

The problem described is caused  by the ears being set too far apart
and the pneumatics moving too fast in making the desired correction.
Ideally the ear valves should both be closed at the same time, ready to
respond to the slightest tracking error in either direction.  Of course
roll widths vary along with humidity at both the times of manufacture
and playing.  Age shrinkage of some roll papers is also a
consideration, but NEVER should the ear valves be adjusted so that both
are open at the same time.

Early tracking pneumatics were supplied with suction through a valve
block identical to that used for the  theme primary valves, but
adjusting valve travel for this purpose proved unsatisfactory.  The
factory quickly switched to button valves, with bleeds in the middle
board of the double tracking pneumatic.  Later the valve block was
omitted and a pouch block added to center the roll and prevent
side-to-side roll movement during rewind.

The size of the constricting bleeds is of critical importance.  Many
times they will be found enlarged as a quick fix for leaky tracking
pneumatics.  I don't have factory specs handy, but anything numerically
under #60 drill size is WAY too big.

Jeffrey R. Wood