HI @zibrz, thank you for reaching out to the Sonos community. I’d be happy to help you all here and it would be best for those having trouble submitting a diagnostic report of your computer for better understanding and see what would be best for the setup. Reply to us with the confirmation number. We and the community are always here to help.

2114525946 I did just submit my diagnostics. Thank you.

The issue can’t be firewall, permissions or WiFi, because I can see everything except the .xml playlists.

Hi @zibrz, thank you for your response and for providing the diagnostic report. I appreciate you providing additional information about your system. Let me help you out with this.

Based on the diagnostic, there's interference in your wireless network that is caused by wireless congestion, and an audio playback failure was detected in your Sonos system. This could be the reason that there's a d as a dropped room. This could be the reason why you're having an issue with your music library.

Let me suggest the next troubleshooting steps, to perform a sequential reboot of your network devices, all your Sonos products, and force close mobile controllers to refresh the connection. 

1. A sequential reboot means that we need to do this in order.
   • Unplug your network devices (modem, router, any wireless access points on the network) from the power and wait for 60 full seconds before you plug it back in.
   • Once the router is back online, unplug all your Sonos devices from the power. Please wait 15 seconds before you plug back them back in.
   • Force close the Sonos app from your iOS or Android device.
   • When the status light on your Sonos speakers are solid white, get back on the Sonos app and check if you're connected.
2. Remove and re-add your music library.
3. Hardwire one of your speakers to your router and update your music library.

If you're still having the same issue, I recommend contacting our Sonos Customer Care support to perform in-depth troubleshooting to isolate if the issue is with the Sub or with the Sonos Amp. 
Our phone support has the tools to check what's going on in your system and to remotely access your device to provide the best option for you.

Please feel free to reach out in the future if you have any other questions. You're always welcome here.

But the issue is not, as you say, a blocked room. All rooms are playing fine, and with no dropouts. Sonos can see and access all albums, artists, composers, genres, song and folders. I think that rules out any issues with crowded WiFi, firewall, permissions, or any other access to my music library.

And as I said before, although Sonos can’t seem to see any of my new exported iTunes xml playlists, no matter what pc folder I put them in, it shows playlists that once existed, but no longer do. As if Sonos has its own cache or something. Solutions?

Hi @zibrz, thank you for your response and for sharing this with us. It seems that you have all checked the settings but unable to see your playlist on your music library. 

We really appreciate the time and effort you've spent doing all the troubleshooting steps, and it would be best for you to continue working with us over the phone to expedite the process. I recommend contacting our Sonos Customer Care support to remotely access your device and perform some tests on your music library to isolate the issue if it's network-related or with the Sonos app.

Please feel free to reach out in the future if you have any other questions. You're always welcome here.