Setting up U-Mix Control Pro 2 for first time

Hey Folks,
I have my U-Mix Control Pro 2 controller set up to CrossDJ version 2.6 running on my MacBook Air and I can't for the life of me figure out why I'm not getting any sound out of the output or headphones! I've messed for a couple of days and it feels like it must be a very obvious solution but I can't figure it out!
I can hear audio through my laptop speakers when I set the software to "Built-in Output" but when I set to the mixer in outputs - I don't get anything going to my stereo receiver. And I never hear audio through the headphones!
What am I doing wrong!? Thanks for helping a brother out...
I have my U-Mix Control Pro 2 controller set up to CrossDJ version 2.6 running on my MacBook Air and I can't for the life of me figure out why I'm not getting any sound out of the output or headphones! I've messed for a couple of days and it feels like it must be a very obvious solution but I can't figure it out!
I can hear audio through my laptop speakers when I set the software to "Built-in Output" but when I set to the mixer in outputs - I don't get anything going to my stereo receiver. And I never hear audio through the headphones!
What am I doing wrong!? Thanks for helping a brother out...