K712 tensioning mod

Anyone have ideas on how I can mod the tensioning mechanism on the AKG K712s? Ideally something friction based that stays where you put it.

The rubber band mechanism is uses it dumb because it always wants to go to a specific height that’s determined by the spring force of the band and weight of the headphone.

So if I could make this bit here to some how grip those 2 rails tightly and only slide with great effort.
k712

Depending on how much space there is between the rod and the slider, you could possibly put a small sheet of thin rubber in there to add friction.