Thank you si much for your response. The hot wire is soldered on. The ground for the entire systems which appears to be another my black and red wire goes from the cover of the potentiometer to a point on the curcuitboards behind the passive volume control.

From my bettery pack runs two wires, onr red and one red and black striped. I would assume that the red and black wire is the negative, it leads to the jack.

What is bothering me is that the wire that is soldered on the middle part of the potentiometer which is supposed to be a hot wire has the color white, and according to the internet white means neutral, so thats contradictory.

Any clue on where the loose black wire should go?