Couldn't that only happen if the clock frequency slowed due to a faulty
crystal or loose loading cap or related fault.

I suppose it could be that or even a mechanical failure (servo motor
problem,
not enough lubrication, spindle off center, spindle bent), power supply
rails at the motor or controller not to spec (too low or too high). I'm
just wondering what the most likely causes are for the scenario that
I've presented.

Mike


--
Diverse Devices, Southampton, England
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