"Server returned 400 Bad Request"

Subject of the issue

When I try to listen to music on Pianobar, the songs fail to load with output "Unable to open audio file (Server returned 400 Bad Request)".

Your environment

version of pianobar: 2018.06.22
your Linux distribution and release version: Solus 3.9999
ffmpeg/libav version and the flags it was compiled with (if you compiled yourself):
- ffmpeg: 3.4.4
- libav: 0.8.21
your config file

audio_quality = medium
tls_fingerprint = [fingerprint]

user = [username]
password = [password]

Steps to reproduce

Open Pianobar and select a station to listen to.

Expected behaviour

Pianobar plays music from Pandora.

Actual behaviour

Pianobar attempts to play all four songs in the playlist, printing "/!\ Unable to open audio file (Server returned 400 Bad Request)" before moving on to the next song. After the four songs, it stops trying to play anything but does not exit.

Other notes

A similar thing is happening on Pithos too. Not sure if Pithos uses pianobar directly or other libraries. I'm guessing Pandora changed their APIs or something?

PromyLOPh / pianobar