I am getting flickers on the hair of the character and also grasses and bushes behind the character while using dof.

What are the settings I can use to remove the flicker?

CTA5, Iclone 7, 3D Exchange Pro, Character Creator 3, Popcornfx plugin, Zbrush, Blender, Vue 2014, Adobe cc suite, Spriter
Homebuild Workstation (Pretty old now but still working great) Win 10, Intel i7 950, 24 GB RAM DDR3, Gigabyte x58a-ud7 motherboard, AMD R9 390 sapphire 8GB VRAM.
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