Focusrite Saf?re PRO 14 User Manual page 27

Unit 1 Setup Cue Mix (unit 1)
Open Saffire MixControl.
Click on the first mixer tab.
Ensure that the mixer output is stereo by clicking on the stereo button (below the meters of the output channel).
Add the analogue inputs to the mixer, and set the required levels and panning.
Add the S/PDIF input to the mixer (this is the feed from unit 2).
Rename the mix to "Cue Mix" (or similar) by clicking on the name field (below the meters of the output channel).
This mix will be a combination of the audio that you are recording (unit 1 inputs), and the S/PDIF output mix from Unit 2 (connected to
the S/PDIF input of unit 1), as shown below:
CUE MIX Selected Unit 1 Analogue Ins SPDIF from Unit 2 Master fader Set to 0
CUE MIX - Sent to Headphones 1 and 2
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