toggle music - phone call

I use my headphone jack to play music through powered speakers. Now I can actually hear the phone ring through the speakers which is awesome. I need to answer the phone call though by powering on the bluetooth which I can do but sometimes it locks up all of the phone call audio

Normally the Bluetooth device would be powered on already to make the connection while the phone is ringing. By powering it on later, the phone app may be having an issue connecting to Bluetooth late.

I've seen different behavior with phone apps that manufacturers put in their layers that go "on top" of Android. These phone apps don't provide a way to automatically change their settings.