When in the presence of lights its possible for textures to begin bugging out on objects and characters, causing small black boxes to begin flickering over them.
I believe it has to do with the presence of extremely bright areas on screen, such as when looking at the sun or having a flashlight close to you as to cause an extremely bright spot where its looking. Attached is a couple videos which showcase my problem.
I've tested this with ArmA Reforger, ArmA 3, and numerous other titles, Reforger is the only one that has this issue. Through research the only other occurrence I've found on the internet of this happening is reported as being someone's GPU being at the end of its life, however for them it was a wide scale issue that was occurring in all of their games. This issue has been reported scarcely by other users through discord and reddit.