I downloaded a video my friend made a little while ago but when I bring it up on Quicktime it only plays about one minute of it anf it stops. The timeline shows only that one minute, but if I play it almost the whole minute then click at the beggining it goes on to the rest of the video. Is there a way to have the full timeline for the video show, so I can jump to parts and not have to let it play all the way through? It's at least 5 minutes long but it won't show the whole thing.