From fiddling about using the crossfader for checking unity on a recorded and live feed, I think the actual settings just require you to set the vol parameter to max on the thru machine.
Thru machine settings:
Input source page AB or CD: 0,
Amp page Vol: +64 (or 63, I can’t remember the maximum)
Track level: 127 (108 default is -3db I think)
Mixer:
Input gain 0 (default settings)
Master track:
Track Level: 127
This should make sure cross-fading between a recorded loop from AB/CD source and a thru audio feed are the same level. You will get a small phase interaction at the midpoint when sliding between the two but that’s just physics .
Note: The VOL on the Amp page attenuates by 12db iirc, so bumping it up doesn’t add digital gain whereas increasing the gain in the mixer source does add digital gain. This may change the tone slightly. If it’s still quiet after bumping the VOL, take a look at the mixer page next to add some more gain. Obviously the compressor gain is fucking nutty on the OT, but that would probably be last to add if it’s still too quiet and you’re not wanting to compress anything as you’ll lose an effects slot.
You can also boost the output of the OT by holding func and turning the level parameter to increase the volume of the master output.