Embedded videos display small in Internet Explorer

Hello! I produced a tutorial for our students and I embedded video from our video hosting site, Viddler. When I originally embedded the videos, I did so using the Flash w/HTML5 fallback protocol, and choose the default as HTML5. Everything looks fine if I publish it and put it in our LMS. However, when I put it up on our website, IE 9 is rendering the videos differently and they appear very tiny and within huge black letterboxes (they display fine in Chrome and FF. I am attaching a screenshot of the issue I am having. I'm wondering if I need to not choose HTML5 as the default, or if I should publish it using the iFrame protocal. Anybody know what the best practice is for this? Here is what it looks like in Chrome:

And here is what it looks like in Internet Explorer 9:

 Any suggestions?

Thanks!