I had the same problem as you have.I got stutters if i had my frames to unlimited or 60 FPS.I had to lock it at 30 FPS.But for some strange reason i tried to set it at 59 FPS as many LCD monitors report 59 Hz,so i tried it just for fun and the stutters went away.I don`t know if this works for everyone,but it worked for me.Bjorn