How can I turn off music automatically starting after phone call in iPhone I use an iPhone 11 with a Sennheiser noise cancelling PXC 550-II Bluetooth headset.

Every time I end a phone call, the iPhone starts playing a seemingly random song from my music library. I understand the benefit from pausing music during a phone call, but when music was turned off before the call, I expect it to stay that way after the call.

I looked, and it seems MacOS has similar issues, but there is no mention (or solution) for the iPhone.

So is it 


Me, because I overlooked a setting in iPhone
some bug in IOS, or
the Sennheiser headset?


I sort of hope for 1) because that would be a quick fix instead of having to report bugs to the vendors.
My guess is that it is a (typically) poor implementation in the bluetooth headset.

I have the same issue with two different cars that are connected to the iPhone via bluetooth. I guess the developer writing the code for the device couldn't imagine that anyone wasn't listening to music, so he hardcoded to start the music after the call ends.

I could not find a solution in many years, and have now disconnected my iPhone from the car for that reason. Obviously not useful for you, as a bluetooth headset that is not connected is useless (whereas the car still drives).