It might be because we use `window.location.origin` to determine the media URL. This[1] post on StackOverflow suggest that only browsers based on Webkit or FF 21 and higher have it. What browser are you using? Can you please file an issue on GitHub[2] with as much information as possible so we can look into it?
[1] http://stackoverflow.com/a/6167979/379195
[2] https://github.com/MediaCrush/MediaCrush/issues