I have an iPad Mini Retina running iOS 8.1.2. I also have a MagicBox II bluetooth speaker. I want to use the speaker via bluetooth with my phone, but I also sometimes use it via its AUX jack with a non-BT capable device.
What happens is I will be streaming via BT from my iPad using Apple Radio, and decide to start using my speaker in non-BT mode. I plug in my other device and the speaker switches and all is well. But my iPad will not stop using BT, and so there is no sound. The music app will not recognize that BT is no longer available no matter what I try. Even turning BT off entirely doesn't help, the music app still plays but there is no sound. Quitting/relaunching the music app also does nothing. A reboot of the iPad will fix this issue.
Is there any way to manually tell the Music app to stop using BT and go back to the built in audio?