Hi there,
Please see the test case: http://www.babylonjs-playground.com/#1YGHUR#0
There are 11 red spheres, the first(nearest) one is made by 'BABYLON.Mesh.CreateSphere', and the rest 10 are instancedMeshes.
At Line 27: the material.freeze() is called.
PROBLEM: Drag the camera to make all the 10 instancedMeshes get out of the view, then you'll see the ground suddenly gets disappeared.
If comment the line 27 ( do not call material.freeze() ), then this problem NOT happen.
Tested Environment: Chrome 55, MacOS 10.12.1
Also tested on windows chrome and mac safari, not found this problem. So it looks a mac chrome only problem.