Sorry to anyone who has been trying to listen to the media files. Mediamax, the website that was hosting them has decided to "upgrade" to something called "The Link Up" and has spectacularly downgraded instead.
I only had a free account and they have decided that anyone with a free account doesn't have their files moved to the new site at all. A disadvantage over paid accounts, but only the very slightest of disadvantages as all the (ignored) screams on the blog of the site seem to suggest that the paid customers' files haven't been moved either...
They are not going to allow seamless linking either so I'm on the lookout for somewhere else to store the files. If anyone has any experience or knowledge (I'm against spending money for this because of the relative unreliability of such services) then I'd be pleased to hear from you!