Apple Music Radio X station not working on Wi-Fi

As of late November, the station Radio X on Apple Music stopped working over my Wifi (and others that I have tried); it will either refuse to start or will play for ~20 seconds and then stop. Oddly, it works fine on 4G/5G.

Other stations work fine, including the effectively identical Radio X UK (Tunein)

This applies to HomeHub, iOS, iPadOS and macOS.

Anyone know why this is the case?