Hello, I've just had the OS reinstalled on my desktop. Previously I had somehow managed to install some birdsong, which was, as it were, ever present. Well, not continuously, but regularly while the PC was awake. Now, I can't recall where I would have got it from or exactly how it was installed. It's not of great importance, but I do miss it and would like to reinstall if possible.
You'll need to play MP3s using a music / media player.
Maybe you previously had some sort of animated wallpaper (effectively the image that you see on the desktop) that included some embedded sounds. If that's the case, we'll be shooting in the dark without more info.
Having said that, you can google "birdsong desktop" and see what comes up. For example Birdsong Radio