There’s someone else that has mentioned this on a Dutch language forum: https://gathering.tweakers.net/forum/list_message/75806652#75806652

I am that Dutch person :)

So I started experiencing similar issues around 2-3 months ago.
Before that Sonos Radio never had issues, other services and local media also play nice :)

Support says Sonos Radio shouldn't be officially supported for Last.fm scrobbling, but I hope this gets on their radar, as Sonos Radio turned out to be one of my favourite services :)

Example, these are plays from 1 listening session on Sonos Radio (A GoGo):

I spoke directly with Sonos support. They filed a bug on my behalf. They have a link to this post so the developers can reference it later.

Awesome, thanks for your effort. Hopefully it will be resolved, as I noticed that this bug made me use the Sonos Radio a lot less, while it is such a great service!

@denleschae Have you heard anything in the meantime?
This weekend still had double or triple scobbles...

@CanisLupusNL No word from Sonos yet. I too still get duplicates and triplicates from Sonos Radio. Still waiting on a fix.

Thanks for the update, hopefully there will be a fix soon.
Sonos Radio is such a great music service, a pity that I now avoid to use it because of having to remove all the double scrobbles...