I have a Sony head unit in my car that has a USB socket and no Bluetooth. When I plug in my iPhone 5C running iOS 10.3.3 into the USB, it starts playing music from my iTunes library automatically.
I do not have a iTunes Match or Apple Music subscription. Neither do I have my credit card linked to the iTunes Store, which could cause accidental subscription to the service.
I do not have any songs synced to the device from my iTunes Library.
I haven't used iTunes Wi-Fi Sync in a long while.
I have a 4G data connection active on my iPhone while in the car.
I have turned off automatic Music download from iTunes Store.
Mobile Data is turned off for music and there is Zero KB of download music.
But as soon as I plug in my iPhone, it starts playing some random song. I fail to understand how this could be happening?
Where is the iPhone getting the music track from? There is no Wi-Fi connection as I am in the car. It sometimes plays a random track from my iTunes library. How do I tell the phone to delete whatever information it has about my iTunes library without screwing up the link between it and my Mac for everything else?