Schlepp, the cancellation effect, in my experience, is WAY more subtle than "do I have to double the power to my speakers?"

Shafer, I think he has to investigate the software's volume settings before adding a single other thing to his system.

It's about gain structure. (That is a term that, taken literally, is incorrect, but it means what it means.) What that means is that all of the signal levels need to be hot enough to transfer the least amount of noise from stage to stage, with all of them being low enough not to cause any distortion anywhere.

Imagine you've got a unit with noise in the output at -60dB. Not great. If you set the audio output of that device so it peaks at -5dB, you've got a little bit of headroom and a noise floor 55 dB down. But if you lower its output to -20dB, you then have LOTS of headroom but you have to turn up some later stage by 15 dB to compensate...and that noise floor will then be 15 dB higher. That's just one step.

I don't think Jim has that problem. I think that somewhere he's got a level that's much lower than it ought to be.