I dont know what type of media it is playing from Safari and I'm guessing its .MOV but after certain videos are played on the mac pro under safari and even closing the safari tab with the video and trying to view movie clips from say gametrailers.com, all of a sudden the video lags and skips frames and just slow. Only when I quit safari all together and reopen safari and watch the same videos in gametrailers.com will it be fast again... Is there some type of codec glitch or bug that causes this with .mov files??