I believe this issue arises from game sounds. This is how I normally fix it without restarting and I showcase the bug a little showing you how I reproduced it. Normally this bug happens to me when a Blackfish with Gunners is constantly firing. http://plays.tv/video/585e48637db55e77ee/believe-bug-for-3fps-glitch-with-arma-3-comes-from-sounds-game-heres-why-normally-when-have-bug-turn