That is not a mechanical problem. As we suggested in your previous post, there can be several causes. Rather than rehash all that, do these tests and show us:
- Mirror cleanliness (*)
- Test scorches at each mirror to verify mirror alignment
- TEM00 tests during both good and bad cutting
- Focus lens cleanliness (*)
That may seem like a lot to do, but the problem(s) you’re describing go beyond mirror tweakage.
If everything on that list looks good, then it’s most likely a power supply problem.
(*) Taking pictures of mirrors and lenses is difficult. Aim the camera to catch reflections from a uniform flat surface so any defects in the reflection come from the mirror / lens. Focus on the mirror / lens, rather than the wall, and make the image as large as you can.