can't get unauthorized guest access to work

The situation:
- Freenas 9.3.1. runs fine
- I want unauthorized access to the directories and files via Guest account without a password
- I have created a cifs share with unauthorized acces through the Guest account
- I can perform all operations on the server from my Windows PC without being prompted for a user name and password
- If I point to the Music folder on the server via my Sonos app i am prompted for a user name and password
- same thing when using my mediaplayer
- If I leave user...

can't get unauthorized guest access to work