See the response from Sonos Staff in this other recent thread, as I suspect your issue maybe related…

Thanks Ken, looks like a wait for an firmware fix

Yes, I’ve seen Staff mention that they are urgently looking into the matter, so we’ll have to see what happens in the next couple of updates -

Meanwhile, it might be worth you still reproducing the BT playback issue and immediately afterwards submitting a Sonos system diagnostic report from within the Sonos App, note it’s reference and then contact/chat with Sonos Support Staff via this LINK and see what the Staff can perhaps suggest. At the very least they will have the information about the Bluesound Node not playing and perhaps be able to check it works with any proposed fix.

Hi Ken

Yes, I will do that, I'd be more than happy to stay fully in the Sonos Environment, great sounding speakers. There is also another caveat with Sonos and the cap on streaming local files from a NAS or whatever no greater than 48khz, have no idea what that is all about, Whereas the Node plays all and downsamples to Bluetooth. So for me I've created another Sonos exclusive folder with only 48 and 44.1 kHz files.

regards

Dennis