This behavior in altitude sounds familiar to me. I noticed this my first couple of times out with the Evo 8 when I first bought it.
While moving the mount up and down at higher magnifications (motor speed was set to around 5, if I remember right..) objects seemed to jump slightly sideways before moving up or down in the field. Motion side to side (alz) on the other hand, was smooth and showed no similar movement.
Mike Swanson’s Nexstar Resource site recommends that while aligning at the start of your session, you should make sure your final movements to center the alignment stars are in the same direction as the final movements of the goto slew. In my case that’s always been up and right in the field, and it seemed to take care of the issue.