I just found the manual hardware volume control!

[MiamiBlue]

Yep it's been staring me in the face this whole time. A hardware manual volume control! Who knew?!
Saves me messing on with the irritating steering wheel controls (why did they have to be touch sensitive AND buttons at the same time?!)
Just need a hardware Skip to next track button now.

 

[Beachbum]

It also stops/start play too

 

[chirowolf]

so where is this?

 

[Nova]

so where is this?

Round knob to the front/right of the shifter stalk.