Hi @Rawcus
Welcome to the Sonos Community!
Sorry to hear of the problem you’re having with your Sonos Beam and surrounds - it sounds far from ideal! As the Beam is basically in charge of what the surrounds play, I believe we should start there.
Please unplug your Beam from power for several seconds, then plug back in and wait for the white bar-shaped light to stop flashing. Once it does, please test playback with Night Sound turned on.
If that has not helped, please remove the surrounds and Sub Mini from the Beam, putting them in temporary rooms (don’t make a stereo pair), then add them to the Beam once more.
Remove surround speakers
Remove a Sonos Sub (Mini)
Add surround speakers to a Sonos home theater
Set up your Sonos Sub Mini
If this does not solve the problem, please get in touch with our technical support team who have tools at their disposal that will allow them to give you advice specific to your Sonos system and what it reports.
I hope this helps.
"Common sense is the collection of prejudices acquired by age eighteen." - Albert Einstein