Master fader and Midi controller

Hi, I use an Oxygen 25 midi controller. This controller has one fader, and it is permanently assigned to the master fader.

Can anyone shine a light on how to disable this? I know about channel and VST quick controls. The master channel seems not to be a part of the channel quick controls…

Thanks!! Daan

Okay, I solved this. Just go to track quick controls, and assign the fader of the Oxygen to a slot. Apparently, without assignment the fader somehow defaulted to the master channel.