As has already been stated the Rear radio runs the speakers. There is a Jensen app for phones that allows you to control the radio by Bluetooth. You can hook up a Bluetooth to the tv and run the speakers, every time you want to watch the tv you have to turn the radio on and it's a PIA to get it to work sometimes.
One member ran an extra set of wires to his speakers and then installed an A/B switch so the tv would go go through them, was a difficult job to run the wiring but it can be done.
Dave & Myra
One day your life will flash before your eyes,
make sure it's worth watching!