Can't Play Song Using "OK Google" on Moto 360 When Phone Screen is Locked

[OMGBosnia]

I recently purchased a Moto 360 watch and have been trying to use the Spotify app on it. I am able to use the spotify button controls and launch the app that is installed on the moto 360, but when I try to play a song using the OK Google voice search, the song will not play if my Nexus 5 is locked. As soon as I unlock the phone, the song starts playing but while it's locked it does not do anything even though the watch confirms that the request has been sent to the phone. I have tried using the swipe, pin and pattern lock screens along with setting the watch as a trusted device. Could this be caused by my location or is there a setting that prevents Spotify from playing a song while the screen is locked? This feature is perfect for changing songs while driving but I am unable to use it at all.