I.e. the scope suddenly moves quite a bit and the guider needs several steps to bring it back in. The rate is <10% but it's pretty annoying.
I looked for hanging wires and all other stuff. So far without success. But when I recently worked with the scope, I noticed that the rotating base of the mount has some play. You can see it in this video:
In this video, I am moving the scope without much force from side to side. Everything else on the mount is very stable.
I asked on the Astro-Physics mailing list for advice...
George from Astro-Physics told me that I should slightly and carefully tighten the tension adjustment screws on the side of the base. I did that ... and haven't seen these issues anymore!!!