I uploaded a song but it is not playing.

After uploading a song I clicked it in the playlist and the download progress percentage ticked up quickly. However, the song didn't start playing. Other songs play fine, so I tried deleting it and uploading it again. Still nothing. Are there gotchas we should be aware of?

Sublimely appealing app you've got here, btw.

(Here is my page: http://thor.muxtape.com/ It is the Iron & Wine song that is not playing.)