I have a 2012 Mac Mini 2.6 i7, running Mavericks. I recently bought a new camera, which of course can record video. My videos when panning have been pretty poor, with lots of stuttering. I put a sample up on Vimeo to demonstrate to a DP Review thread, and it played fine. So I went back to look at other playback options on the Mini. VLC played smoother than Quicktime, but still a bit jerky. When I put it in iTunes and played it on my HDTV through AppleTV, it played perfectly with no stuttering. Same with iPad, implicating the Mini. Just to be sure, I went to an Apple store and tried it on a variety of computers, including a lower spec Mini than mine. All played perfectly. So what's wrong with my Mini? I don't have a clue as to where to start looking, though I did check memory.