Printing at 100 microns, halfway through the print a hitch developed in the movement of the resin tank. Between each cycle, the tank would jerk violently 2 or 3 times before continuing. The resin tank and the mixer arm were both firmly and correctly attached. The pring continued, but the final product was slightly distorted, not as tall as it should be. Any hints on what the problem might be and how to resolve it? Thanks!!