Hello @Grrr, welcome to Sonos Community!
Please have a look here: https://www.bbc.co.uk/sounds/help/questions/playback-issues/sonos-help
While Alexa works on Sonos devices which are voice enabled, BBC Sounds is not yet supported using Google Assistant. However, we are in discussion with Google and Sonos to find a solution and enable this feature.
You will need to reach out to Google, as they are responsible for the integration of Google Assistant on Sonos and its features.
Apologies for the late response and I hope this helps.
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