Black models in Viewport

[moondog]

Hi Guys

I have a strange issue, tried googling it, but couldn't find a solid solution.
Sometimes, when changing views, my model would appear black in my viewport (see attached).
The only way to get it back to normal, is to change the viewport quality from Standard to Performance(or anything else for that matter) then back to Standard.
Happens in Default Shading.

This only seem to be happening with Nitrous Direct 3D 9 and 11.
Anyone know of what could be causing this?

I don't know if its coincidence, but it seems to start happening when I switched to Corona, but then again, this was around the time I started using 3ds Max 2017.

GTX970 - Drivers up to date
Happens to textured and un-textured models.
Display color has no affect.
Not backface cull / flipped normals.

Thank you in advance

[mferster]

What happens when you change the viewport shading to a different mode? any difference?

[moondog]

All the other shading's work perfectly, but as soon as I switch back to "default shading" its all black again.
I've gotten use to working in Clay Shading because it never goes black in that mode.
Just very frustrating when you're texturing and, every 3 - 5min, having to change the Shading Quality from Standard to anything else to back to Standard to get things looking normal again.
I've gotten to the point where I've set shortcut keys for switching between "Standard"and "Performance" to refresh the model.