When I'm listening to Spotify (and even when I'm not), I get a notice in my phone's status that says "Casting to <device name>". There's a pause button and a mute button. The pause button (rather than play) makes it appear that I'm currently casting to this other device, and I definitely don't want to cast to someone else's device. I've looked everywhere in the app and can find nothing that would disable the automatic casting. If I click the pause button, it changes to a play button (making it seem that I've disabled it), but next time I open my notifications, the pause button is back! It's ridiculous that casting to another device without my permission would be the default behavior. If I can't disable it, I'll probably cancel my premium subscription...