With the phone in my pocket, I press the command button on my Bluetooth headset (Gear Circle) and saying "Play Bastille" returns a friendly voice "Ok! Using Spotify to play Bastille" but nothing happens.

Only when I turn on my phone screen do I see Spotify, with Bastille in the search box and Oh! Suddenly it starts playing!? What is that!? Do that without me having to turn the screen on!

I thought it night be to do with having Stamina mode on (my Sony Z3) as it sometimes disables internet when the screen is off, but switching off Stamina mode doesn't help.

So close!