I have a frame assembly made up of a number of sub-assemblies (panels). When I zoom in on one of the panels, it begins to progressively and discretely disappear as I get closer - i.e. some components disappear, then as I get closer, more and more. It is almost as if I am passing through some plane that you can't see beyond. It is only one sub- assembly that is consistently affected, and it doesn't happen when I have the sub-assembly open, only in the overall assembly.
Any insight on this would be appreciated,