Good day, I have had the 913 nightmare too. I no longer have the issue..

Sonos Play 1 stereo pair 

Windows 11 Laptop

Sonos s2 Latest version

Ensure the music to be shared folder is in MUSIC on the C drive. Clear all previous shares in Sonos Music library.

Ensure all share permissions are granted on your folder placed in MUSIC (properties Sharing etc)

Restart Sonos and reload your library. I know its simple but it worked for me after the recent shambles 319.

Its been good for three days now. My Sonos app will not work anymore with Music stored elsewhere on my pc.

I hope this helps.

Moderator edit: Corrected 319 to 913 for clarity