video problem

everytime i watch a video, it buffers.. but after a couple of seconds the stream bar(the blue one i think) completes but the video itself is incomplete. like for example, i watched consenting adultery:

*it buffers. and you'll see the intro Milky.then the stream bar is completed but it really isn't. And the video stops on the Milky part. then it does not buffer anymore. pls help.