[QUOTE 3380495, member: 259"]No, there's no console information on Spotify (running Yosemite and Spotify 11), apart from the standard stuff when the application opens or an exception is recorded.[/QUOTE]
I've just tried (identical setup to you) and it seems either the latest Spotify update or Yosemite has broken it. But some googling has solved the mystery: the app allows you to toggle on High-Quality (320kbps) when you have a Premium subscription, refusing to do so for a free or Unlimited one. However, once it's toggled on, it stays on when you downgrade.