video playback speeds up if you fastforward

hi, my video playback will speed up if i try to jump somewhere in the video. using ATI file player. to play .MP2 (6meg/sec rate) adobe premeire 6 also does it, its not everytime, but about P. anybody know whats up?. i tryed to reinstall ati. but no luck. Im using a P4 with Radeon 8500DV 256M PC2700 XP Pro - with latest drivers.

when playback speeds up i cannot slow it back down. need to restart video.

OH and Quiktime will not play them .MP2 it says that a component needed by the movie could not be found. any body know what file im missing? ive tryed to reinstall it with no luck. --- quicktime should play them right. I capture them in "ATI TV"