When I select an object, and use my hotkey (i) for ‘hide unselected’, my unselected objects disappear as they should.
BUT - when I try to navigate around the object using ALT+LMouse, I get no response from mudbox.
My second attempt to navigate results in all my objects re-appearing, and the navigation movement gets stuck to my mouse movement (no ALT key, or mouse button input required).
Hitting escape allows me to exit this funk.

*If I deselect all after using my ‘hide unselected’ hotkey, I don’t get any problems.

i have some similar…

Ctrl+L in my cfg hide unselected and when try to navigate (alt+LMouse) all disappear… i fix it using ctrl+z (bring back the selected) but its annoying

Does this happen consistently with all scenes and with default Mudbox geo?

I figured out when this problem happens.
It only seems to happen with high-poly meshes which have no levels.

Here are the steps to reproduce it:
-create default mudbox geo (I tried both sphere, and cube)
-subdivide geo to a high level ... 100,000+ poly’s..the more the better
-export the object as an obj
-create a new scene and import the obj
-select a patch of faces, use hotkey for ‘hide unselected’, try to navigate using ALT + LMouse