I have setup the air channel to be my sound blaster express card.
I have setup my headphones to be my cue channel.
The problem is the AIR channel still bleeds into the headphones so I can't hear the cue channel well enough.
Are you playing to both channels at the same time? I don't see how you would have an issue where it's that loud unless you're playing the air source to the cue at the same time. Anyone else have ideas here?
By Default, the Ots Output configuration window shows a slight mix. You will need to make sure you alter the mix setting to zero to remove the mix as shown in the image below...
Is second that. Personally I like a bit of the main mix in the cue for beat mixing, but it's entirely up to you where you set it. Unfortunately, this adjustment is not exposed to MIDI controllers.