Some tree-meshes, placed by foliage (paint or spawn), it’s moving … litteraly changes position when point of view move out away from them. Look the video … both groups, left trees and right trees, are foliage painted … and have same settings, even so, the right group of trees work fine… but the left group, as you can see, has this bad behaviour.
Could it be that further level of detail objects were imported with a smaller scale?