I have a strange issue using Rhino with an external display connected to my Macbook pro.
Under certain circumstances when moving the mouse around, the external display will turn off and on again. A sure fire way to trigger this is to start drawing a curve with Polyline or InterpCrv, place a few points and whilst still drawing the curve, mouse over some of those points. The display will then turn off momentarily (about 1-2 seconds) and come back on. This only seems to happen when hovering over points with object snaps enabled. With object snaps disabled the problem doesn’t happen.
This only affects Rhino and started maybe a couple of months ago. Has anyone else experienced this? Google hasn’t been any help.