Plug it into charge where?
The USB port on your radio/sound system might charge, but it's priority's are for reading files and playing music, that shuts off the blue tooth, to receive sound thru the USB port
Get a 12v charge cord and use that to charge the phone, not the sound system usb Port
That should fix the problem
You are telling the sound system forget Bluetooth and use the USB port
It is connected to a media device
I can explain it to you.
But I Can Not understand it for you !
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Connected using T-Mobile Home internet and Visible Phone service
1997 F53 Bounder 36s