No Spotify on Pirate Audio

Hi all,

I’ve bought an Raspberry Pi Zero W with a Pirate Audio line OUT and I set it up but Spotify doesn’t work.
When I try to play a song on the server with Spotify Iris says "Mopidy: Failed to add some tracks"

Can someone tell me how to resolve this problem?
I’ve have done everithing that’s write on the setup page of the Pirate Audio.
I’ve bought this board only for this function but it doesn’t work…

If there’s need some log I can retrive it if someone tell me how I can do this.

Thanks to all.