Hello @David_Hunter ,
Thanks for the additional information you provided. I took a look over your latest diagnostics and it looks like the issue is still stemming from the same device, the Bedroom Left zone is having dropouts, and it is causing the entire group playback to fail.
Can you provide some more details as to how Bedroom Left is connected/located? Is it in a cabinet that could be blocking the WiFi signal? Is it further away from the rotuer compared to the other endpoints? I would also suggest performing a factory reset on the unit and ensuring that it is on the latest firmware version, in case this helps. I was able to locate the following article from Bluesound on how to perform the reset:
Let us know if this helps, and how the physical traits of how the device connects to the network.
Also to note, you Motorola MG7550 is an ISP router, and we have seen that ISP routers are often under-powered and fail to perform as expected. You don’t need to splurge for an Eero Pro 7, but any recently produced consumer-grade router (Asus/TP-Link/Netgear, etc.) will very likely provide you a much better experience, and you can leave the Motorola in modem-only mode (Bridge mode). The below thread discusses some popular router options amongst our customers: