Can't believe no one has talked about this. The best way to utilize interface outputs (especially with counts as low as on PreSonus interfaces) is to send mono cue mixes out to headphone amps. If I can't select single, mono outputs for cue mixes and sum the panning to mono (like all stereo outputs can do already), then I'm essentially wasting a second output as a duplicate of the first cue mix. On a mixing console, that problem would never exist, because mono outputs just ignore panning or sum to mono. Studio One should be able to do the same.
