Hi everyone,
I had multiple Sonos devices throwing error 30 this past week with the update to Sonos v14.9. I tried everything on this forum, including factory resets (about 20 times), unplugging all devices but one working device, plugging devices directly into router with ethernet, even trying to setup a new System in the app.
Eventually I discovered the issue was due to using a CleanBrowsing DNS filter on my router. The solution was to go into my DNSFilter router settings, and override each of the affected Sonos devices to a “No Filtering” filter mode.
With the DNS filter enabled, the system could see the updates but was unable to apply the update to the Sonos devices. Essentially the devices were bricked. When the filter is bypassed on each Sonos device, they are able to function and update as expected.
Hope this helps someone else with similar issue.