Playing music audio through bluetooth in car

I have a third party bluetooth device installed in my car. I'm not sure exactly what brand or model it is, as it was already in there when i purchased my car. The little gadget it pretty basic. It only has three buttons, the bluetooth symbol, volume up and volume down.

I'm able to connect my phone to it, and it works when i get a phone call, when i make one or when i use siri. But i can't play music or any other audio through it

does anyone know how i can make this work?
( i have a 2007 VW golf and an iPhone 7 Plus)

Maybe your device is only meant to handle phone calls. Otherwise you would just start your music app and it would play through the car speakers.

Most older / simpler Bluetooth devices are for hands-free voice only.

Hands-free calls (limited quality, mono audio) and music quality stereo audio are considered to be two totally different services in the Bluetooth specification.

You need a different unit - or a radio with built-in bluetooth - for full stereo audio support.

Hi so first off this age of car would not have any type of bluetooth device fitted as standard. Thi is a retro fitting. As you want more you will need to get a more up today device fitted which is going to need power from the car's battery. Such as a new stereo system.

Put a bluetooth transmitter on your phone's output and pair it with the car's bluetooth. That gets your music. It might interfere with phonecalls. Try and see.