Question / Help External audio input routing issues

HI All

As a sound engineer and music producer i tend to think im fairly good with laptop audio routing but this ones stumped me so any help would be greatly appreciated.

I'm using a focusrite saffire pro40 to route a stereo line signal (from my DJ mixer) directly into OBS. its routed to analogue input 1+2 and i can clearly see via the hardware and associated control software that there is signal coming in.
I then routed mic/Aux 1 within OBS to be my Saffire interface and other routing options past this are available i assume it will route inputs 1+2 from here to be 'tracks 1 and two' as shown in the advance audio menu. In said advanced audio menu everything seems to be 'active' although i notice there isnt any panning options for the input?..
I also disabled all other audio inputs but this still seems to result in me getting no audio from the interface into OBS?

To check its not an audio issue in general managed to stream some desktop audio in fine.

Any ideas? Ahppy to send through a log file too but not fully sure how useful that would be (although im not programmer so correct me if im wrong).


Kit list:
Macbook pro late 2015 - 2.2ghz i7 / 16gb RAM / 250gb internal SSD --> OS 10.13.16 (high sierra)
Focusrite saffire pro 40 (firewire interface) + Saffire mix control V3.9 (latest firmware)
OBS V25.0.8