I would first try a sequential reboot of your network and devices to eliminate the potential for it being a duplicate IP addressing issue, which is what it sounds like maybe happening here, but that’s a guess at this stage based on what you’ve mentioned in your initial post.

So perhaps try this …

Simply switch off all and switch them back on in this sequence:

• Modem/Router
• Boost or Other Cabled Sonos Speakers/Devices
• Wireless Sonos Speakers/Devices (nearest first, to the furthest away from the router)
• The Sonos Controller Device(s)
• Your other network and home devices

Allow a couple of minutes for each Sonos device to establish a stable connection before moving onto switching-on the next device. Let your 'rebooted' network settle for 10 minutes or so and then run your tests to ensure everything is then working as it should be.

Thanks, but… the only difference was I restarted Sonos devices from furthest to closest.

If the most distant SONOS is not wired and is beyond wireless coverage from another SONOS unit, this sequence might not work. 

That would be weird because the wireless radio is the one thing that has worked flawlessly for five years. Until yesterday.

We cannot rule out hardware failure. Another possibility is a neighbor installed something that causes interference.

I would understand if interference was impacting one speaker, but this is at the interface level?

Hi @Alonzo Mosley 

Thanks for your post!

The diagnostic is reporting a possible issue with your Boost’s ethernet cable (I say “possible” because it’s possible you unplugged the cable 3 times in one minute intentionally), so I recommend you try a replacement.

I hope this helps.

It’s a fairly new cable. I had rebooted the router and unplugged the speaker “recently” before the diagnostic - would that present the same? Or is that definitely tied to a hard CAT link?

Hi @Alonzo Mosley 

If by “unplugged” you’re referring to the power cable, then that is not what the Boost is reporting - it’s reporting 3 ethernet cable disconnects in the space of one minute.

Sometimes I find that new cables are difficult to fully seat in the jack -- leading to intermittent connections.

I just had this issue. I tried everything I could think of. Finally I decided to reset the speakers one at a time. After I reset the first speaker the system was fine all over. I can’t figure that one out.