Screencasting of a Silverlight Application?

I have got a silverlight application which basically plays videos among other things, as is portrayed below (Silverlight 3):

<Grid x:N开发者_JAVA技巧ame="LayoutRoot" Background="White">
    <MediaElement AutoPlay="True" Source="World.wmv" />
</Grid>

But, when I 'screencast' it, using Microsoft Expression Encoder 3 Screen Capture the output video is jagged, and seems like it is recorded at a very low frame rate, while when I 'screencast' a site (for example) one made by the 'Job Output' of Microsoft Expression Encoder 3, it records and plays back at a normal frame rate. Both of the recordings are done with the same settings with the only difference being the code, and work perfectly when viewed in IE8, so I was wondering if there is a property in Silverlight that you need to set, change, etc. that it the Silverlight application gets 'screen casted' correctly.

Thank you,

Update Else, is there a way in which you can export a silverlight page to a video file, or similar?

I have found that there is no problem with Silverlight (or my code), rather it was that may laptop was way to underpowered and using a (more) powerful computer heped.