Some scanning and possible hardware issues. 80w red & black

It seems I’m having some hardware issues with my chinese 80w.
Started out with no problems, then scanning offset went to .25, and now it’s up to .6.
But there’s still some line issues.
I’ve tried belt tension, calibration in RD works, all sorts of things.
I’ve included some pics of the issue.
I think the first two speak for themselves.
The last one is a 200x10mm rectangle

OK, have re aligned every belt and pulley and now my issue is the pairs of lines.

This pic

is with the fill set to .4 on a 200x10mm box in lightburn.

a 100x100 box is exact using a micrometer, and verniers.