Ah, so, I went into “Battery” and other modes… App Management and selected “Google Play Services” to be kept on! Now it is working! Thank you sooo much! Please do let me know if there is another way to “lock” apps , as it would be useful to know.
It is now working! YEY!
No, mine just use to stop after 3 mins. Then, say I went to the car after a few hours, it would default back to the default Music player.
It still sometimes does that, which is annoying, I would delete it if I could, but then I think I have to root the phone.