Pumpkin volume control

[SQueal]

I am new to the forum and new to having a Pumpkin head unit.

I have recently bought a Pumpkin 10.1 inch (upgraded version as listed on Amazon, AS0274B-02A) that has the fully articulated screen, Android 7.1, 2Gb ram. My previous stereo was the Parrot Asteroid Smart.

I installed an app that is able to adjust the volume based on GPS speed. After I set it up, I went for a drive, messed around with the volume and realised that it wasn't updating the volume. I have installed another app to check the various volume sliders, and with the radio or music running I have adjusted the volume slider of each item, i.e ringer, media stream, bluetooth, etc and none of them affect the volume.

My question is does anyone know what the on screen buttons, or the volume control knob are actually controlling, and therefore can I install an app to do this? Or does anyone have an app that can do this of a Pumpkin head unit. It seems on that the standard volume sliders to not control anything.

Thank you for any help or information anyone can give.