Hi nickvas19 & hondagx35,
On my Pi B+/zero version with an updated kernel Spotify works fine.
My Pi 3B version with an updated kernel (build janui-20171120) which is based on the v0.3-beta (23/03/2016) RuneAudio_rpi2_rp3_0.4-beta_20160321_2GB.img.gz Spotify will not work.
But I do know that Spotify has worked on the 0.3-beta (23/03/2016) RuneAudio_rpi2_rp3_0.4-beta_20160321_2GB.img.gz. But I don’t have this version installed at the moment so can't test it now.
Very strange.
janui