Streaming Radio - Disappearing from Playlists!

After owning ATV2 for a few days, something really frustrating has started to happen. When I add streaming stations from iTunes Radio to a playlist they no longer show up on the ATV when I choose that playlist (No Songs Found error). The first day or two it seemed to work ok, but not they don't seem to show up no matter what I try. I've tried having the playist synced or non-synced, restarting itunes, restarting the ATV, creating new playlists, adding the stations again, trying different stations...and every possible combination of the above. Is it possible that Apple somehow "killed" support for this? I really hope to get this working since otherwise ATV is pretty much a giant paperweight in my book. We listen to streaming radio about 80% of the time and I really don't plan to use the movie rental feature all that much if at all (more of a music server for me).

I'm running the latest version of iTunes on WinXP and have tried connected both via wireless-G and wired ethernet. Any advice or ideas appreciated. Thanks.