I turned off everything one at a time. Turned out i fiddled with the gradient in the HDR Studio Rig and made it a really harsh transition. I added a new HRD Studio Rig and left it to default settings for gradient.
Problem solved!
G. Weglarz
MSI Intel I7 5960X 16 Core @ 4.4GHz; 32GB Ram;
NVidia GTX 780ti; 60TB storage; Four Asus 27\” monitors
Adobe CC 2015
Cinema 4D R16