Hi @RobOK ---- Thank you for the follow up, I received your PM and have asked you for some additional information in regard to your network configuration.
Moving forward, I would like to kindly ask you to please run the following test to see if we can trigger a change in behavior here. Please see below.
In your PM, Rob. You mentioned the following:
When Roon loses the end point, it really loses it – it still shows, but can’t get it back. This has happened only with the Playbar/Connect/Sub grouping and the Stereo Pair Play:1 – I assume it is a coincidence that the ones it has happened to are groups, but thought important to say. (By group I mean done in Sonos not Roon)."
Please use the instructions found here on how to launch Roon with the mentioned “command flag” (see below) and confirm if you notice the same behavior with your various Sonos zones.
Let me know how it goes!