My iMac (intel) is having serious problems playing saved video files, especially from the Elgato EyeTV hybrid (file extension .eyetv). Everything played fine for about 1.5 years, then suddenly the iMac just started pinwheeling intermittently and stopping the video every few seconds. It was like watching Youtube on dial-up. I tried closing programs, stopping Time Machine, restarting, reinstalling EyeTV... but nothing fixed it, it only got worse and actually started freezing the whole machine and causing incredibly slow and scary restarts with lots of blue screens. At this point I actually re-formatted the whole darn computer and the files played OK for maybe a day or two, then just started pinwheeling the .eyetv files again, although movies on my hard drive play ok now as far as I know. Youtube and other streaming has always been fine. Watching live-feed TV on the EyeTV has never been a problem either. Why can't I watch my recorded files?