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[Mudbill]

Does this happen when you use just the normal "high" setting without v-sync?

I heard that setting the SSAO to max would require a great deal of processing power without really improving the graphics much. I suggest just using the defaults there (16 + medium).

Also, what is your monitor's refresh rate? V-sync is supposed to prevent tearing in the screen caused by unstable framerate in-game, and therefore limits it to the refresh rate of your monitor (because having 100 fps when your monitor can only display 60 is unnecessary in many cases). Most monitors have a refresh rate of 60 Hz (which is 60 fps). If yours is lower, v-sync will lower the fps. V-sync also supposedly requires some processing power as well, so if you lag, turn it off.

Other than that, the issue could of course be something completely different, perhaps with the sound cache or whatever.