Android 7 phone once paired with earphones or car headset disconnects and reconnect, causing annoying drops in music play
My HUAWEI 3a drops off the car phone system. I had replaced the car system to overcome this issue previously but it still did it.
Eventually found that when the phone went to sleep (in my case 2 min) it shut the bluetooth down and any calls ceased.
I reset the phone to 30 min which is the longest it goes to and now no problems.