NAS for Sonos

[ed]

Yes, any NAS will serve as a source for Sonos library. J series are quite weak NAS, but it will do the job.
Here is how you can switch between compatible SMB mode - https://nascompares.com/answer/smb-v1-co...for-sonos/
Here is a little more - what it is https://nascompares.com/answer/what-is-s...enable-it/
And a little more about FLAC audio https://nascompares.com/answer/flac-musi...ic-system/

I hope this helps.