After researching, tracing and trying multiple config changes finally got my Sonos S1 working with TrueNAS-13.0-U6.2. Here my configuration, hope it will helps others:
Services / SMB:
Enable SMB1 support: checked
NTLMv1 Auth: checked
Guest account: nobody
Auxiliary parameters: unix extensions = No
Sharing / SMB:
Name: Music
Path: </your/path/to/music>
Purpose: No presets
Enabled: checked
Enable ACL: checked
Export Read Only: checked
Browsable to Network Clients: checked
Allow Guest Access: checked
All other checkboxes: unchecked
Auxiliary Parameters: public=Yes
Sharing / SMB / Share ACL:
Share Name: Music
SID: S-1-1-0
Domain:
Name: Everyone
Permission: FULL
Type: ALLOWED
Then on you Sonos S1 phone app, go to Settings and "Music Library Setup" and add:
//<IP_OF_YOUR_NAS>/Music
(leave user/passowrd blank)
