Windows Phone 7: Seeking in MediaElement

Question

I'm working with a MediaElement for Windows Phone 7, and I want to make a simple slider that will allow a user to seek within an mp3 file. I can't quite get the behavior I want though. When I seek a short distance forward, it will work fine. But if I try to seek to the far end of the media, it will no longer play and go silent. Is there some sort of buffering that is occuring under the hood that is preventing seeking long distances? Has anyone overcome this issue or found a solution?

I've been referencing this post on msdn for info, but my URI is coming straight from media included in the xap file, not being transferred over a network protocol. I am also using the MediaElement.Position property to seek.