that a crown built mast?
or is it a lifttek mast built for crown?
from your problem description and test results it sounds like it may be a channel sequencing problem.
First thing i would do is check the chain adjustment on each section.
one section out of adjustment can cause this.
the drift your seeing might be the channels just settling down trying to equal themselves out. You will see it drift for a bit and then it stops?
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