Is this an S1 or S2 system?

I see you mentioned that you have already factory reset the device, aswell as cabling it, to your router. Does it then add back to your system whilst it’s status LED is flashing green, or do you get the error mentioned during the actual setup?.. if so, maybe try a different Ethernet cable/port and see if that might resolve it, otherwise it might be a hardware error, in which case it might be best to submit a system diagnostic (if you are able to see the speaker in the App) and note or post it’s reference back here and then contact/chat with the Sonos Support Staff via this LINK and see if they can see any issues with the device.

I don’t think that we can rule out hardware failure. It’s possible that the update process attempts to use a defective area of RAM that is not used during normal operation. It’s also possible that a future attempt will not stumble into this area.

Thanks for the responses... After it failed from both desktop and mobile app and with cable connected I checked my router app... Just to find one of the Sonos devices paused for some reason... Unpaused it and next attempt was a success... So good for now. But that still doesn't address the issue with devices being rendered not usable once a software update appears... 

Paused because of duplicate IP addressing perhaps? - what might assist here, is to add your Sonos product IP addresses to your routers DHCP reservation table, that’s assuming you haven’t done that already?

Hi @thomaswo, welcome to the Sonos Community!

Update Error 30 occurs when a device tries to update but isn’t able to download the new firmware, usually caused by network settings blocking the update or speaker from accessing the updates. As you discovered, your Play:5 was paused in the network, which is why the error was appearing.

Regarding the speaker not being usable, this is because the update was triggered but not completed. As it’s in the middle of the update process, it would be unusable until that finishes to prevent any issues with your other Sonos devices. 

If you don’t want this to happen again, then you can turn off automatic updates on your system by going into your settings → system → system updates → then toggle automatic updates off, however I would recommend keeping the updates on and troubleshooting if any issue does arise. 

I hope this information helps!

Omg, thank you, thank you, thank you, THANK YOU for this!   I have spent hours on the phone with Sonos tech support and XFinity to no avail.   This fixed it!  Auto-update goes off from now on.