Mopidy 3.0 has released recently (December 22, 2019: https://mopidy.com/blog/2019/12/22/mopidy-3.0/).
So I could not run normally Pirate Audio with the current software and installer.
I uninstalled mopidy 3.0 and mopidy-spotify, and then installed mopidy=2.3.1-1 and mopidy-spotify.
Then finally I have been able to run Pirate Audio normally.
Do you have any plan of Pirate Audio for adjusting to mopidy 3.0?