I appreciate all the tips others have posted for connecting Sonos to Synology NAS on a Mac. I went through the dreaded screens in Synology File Services to add SMB1 and NTMLv1, and then restarted my NAS. But that still did not let me add a music library. On my 3rd call to Sonos Support, the Agent had me go into Mac System preferences, Security and Privacy, and then add Sonos to Full Disk Access and to Accessibility. That did the trick.
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