MR816X Master Knob controls all outputs?!

Hello everyone! I´m trying to create a simple external FX routing to my pedals. I´ve noticed that this only works if my main master knob on MR816 is up! All in All, the Master Knob controls ALL the analog outputs and not only the ones I set to be my Monitor Out 1/2! Is this intended to be that way?!
How Am I suposed to do a simple external FX routing without the need to open my main monitor?
ps: there is nothing on the audio MR816 hardware setup inside cubase that helps me with routing, and MR Editor does not work when cubase is open.
Is routing the output via control room being the issue here?