It seems at the first time I did not understood correctly the usecase.
So you want the use the uTrack24 in interface mode? (like a 24/24 sound card)
The connection depending on your environment and external gears sorry but I cannot tell you more.
The only thing what can I tell you the uTrack24 has balanced inputs and outputs. If your connection balanced you can use DB-25 to TRS jack, if the connection is unbalanced you need to use DB-25 to unbalanced connection type. You can find the DB-25 pinout in our FAQ