Latch - Sum Control room inputs?

Is there a away to have Sum or Latch the inputs , so you can hear 2 audio sources at once ?

Screenshot 2023-02-16 at 11.08.11
Screenshot 2023-02-16 at 11.08.07

Not sure what you mean as you are looking at outputs there and not inputs

They are the inputs into the control room , mix is your mix and Ext i use with a Cd player for referencing .

Not that i’m aware of .

I want to monitor two sources at once in the control room, so I would have my ProTools rig, returning into Cubase on here both at the same time

This is how Eucon does it . Sum = More than one Intercancel = One at a time