Update: We’re getting info that confirms the below, so give that a try; if you have trouble still, we have embedded a player into this post for your convenience! Essentially, if you are experiencing this issue it is because you have an old entry that is linking to a file that does not exist.
We have heard that a few people are having trouble accessing the show in the U.K. via iTunes and RSS. Our best guess is that it is a cache issue on the user end.
I did have to adjust something in the feed overnight in the US (or, morning in the U.K.) so it’s possible that you have an old version of the episode in your iTunes feed and a cached version in your RSS. I recommend refreshing both of those, and clearing your browser cache if necessary. I have verified the file is accessible in all locales so the fact that I had to do an in-place change of the episode overnight is the only explaination I can come up with.
This may be as simple as deleting the episode and refreshing but also could involve deleting the episode from your feed, unsubscribing, manually killing the app, and resubscribing.
Thanks for alerting us to this!
In the meantime, try a direct link to the file: