Connecting qc to audio interface very quiet?

Hi @russ and welcome to the community. Honestly, I’m not sure what you are asking etc.
Otherwise NDSP recommends for best SNR to use the big volume knob at 100% and then tweak presets as needed. If you are using another interface for audio input besides the QC, I would consult the manufacturers manual for that interface as you may need to bump up the input gain.