There is problem when trying to play different fps videos like ntsc videos (29.97 fps), it drops some frames and stuttering video. So, flex video components have a default video frame rate? i think it is only reading 24 frames , not reading other frames and so stuttering.
Tried it with s:videodisplay, mx:videodisplay, flash.media.Video, org.osmf.elements.VideoElement components and all of it the result is same it is not playing ntsc videos with real frame rates and stuttering. Also tested different videos all is playing very well on windows media player-vlc etc.. but stuttering on flex-osmf video components.