Buffering at 4% forever

I have last.fm on my iPod Touch. Earlier, I went out of wifi range. Since then, whenever I try to start up a station, it shows a song title and "Buffering..." A few seconds later, "4%" appears below Buffering. It never progresses from there.

Have tried restarting the application and the iPod, as well as logging in and logging out. Any help would be appreciated. You guys rock!

Thanks,
Ben