Any suggestions for pairing a OnePlus 3 with a (2016) BMW for audio? Mine works like a champ for speaker phone but in order to play any kind of media, the OneP

Any suggestions for pairing a OnePlus 3 with a (2016) BMW for audio? Mine works like a champ for speaker phone but in order to play any kind of media, the OnePlus refuses to do it. (Though my son's Samsung Galaxy S5 works.)