Give me an example URL. This is what I do for a living (run operations & lead technology for a major online video production group, specializing in on-demand and live streaming) - I can probably help.
PS. First suggestion is trying to turn off hardware acceleration (right click on video --> silverlight preferences --> Playback --> hardware acceleration setting at the bottom). Using your GPU to decode videos can sometimes cause scrambling.. The videos I find on hudl work fine for me (on my Mac), but not sure if it's the same player you are having issus with.
