Stutter in Full hd video playback

Hi, my z3 tab has some problem in the playback of 1080p movies (mkv or mp4), i want specify that it is an issue that someone can not notice, for example my wife see movies witout problem, but i ham more accurate and see that video is not perfect fluid. I have the last version of lollipop and i have tray thestandard player and vlc and bs player, but have same performance in all. Any sudgestion? Thx