I never said it was a design flaw. and it’s not an issue with the machine, so far I think it’s a slicer issue. the middle z that I am using is the original beta middle, that most of you have never seen. it’s the middle that was going to be the new middle, but it was flawed and was totally redesigned. sat first I thought maybe it was the problem, but I just printed a 40mm test cube at 90mm/s with acceleration bumbed waaay up and I still could not reproduce the problem. so I’m trying a different slicer now.