For more than two years I had no problems. It startied all of a sudden. I noticed sporadic image distortion during session. Sought it is related to the latest ZWO driver I installed. I installed previous version. Same thing. Tried new cables, new USB3 hub, check all voltages. Nothing helped.
It happens sporadically maybe 5 - 10 times during 150 - 200 subs session. Didn't see the problem during short exposures when you aim the scope on the target. Only on 120sec subs that I normally use. (At least I didn't notice it when focuse,and point on the target) .
My configuration: Acers R7-571 laptop 12Gb RAM 512GB SSD USB3.0 mini hub, ASi120mini gyuide camera, Pegasus Astro Fucuse Cube2, Skywatcher EQ6 Pro mount and 12v 15A power supply. I use Astrophotography Tool and PHD2 to get subs.