Could you try and use an action event for playing the music instead of "on start of layout", something like on click sprite play music etc.
check if it starts playing as soon as you click it then.
Just one more thing - what is the best way to have the music loudness changed during play? I have a variable sfx sound and music sound which is basicaly the volume for the different sound tags. However i dont want to have "every tick" event for the loudness to check. And if i change it to something else, it didnt worked so far...