As I understand it, in Logic X, if a channel is selected and the volume fader is adjusted, then midi info is send to the preamp gain control on the Studio 192. Conversely, if the preamp gain is adjusted (either on the unit itself or via Universal Control) and a channel is selected in Logic that has that preamp as input, then the volume fader of the selected channel moves in Logic.
There is a post on the Sweetwater website that addresses this: https://www.sweetwater.com/sweetcare/articles/why-does-the-preamp-knob-on-my-presonus-192-make-a-fader-move-in-logic-pro-x/
Unfortunately, the prescribed solution doesn't seem to work for me and it also seems more like a hack solution anyway. Is there a way for Logic and the 192 to NOT communicate midi data or something?
I'm surprised I haven't found anyone else asking this question as it seems like a really big deal to me. Like, I can't track like this. The mixer faders in Logic are fundamentally not preamp gain controls.