Mic to Mackie Onyx Blackjack to Mac, Not Recording

[wtd2200]

Totally lost here.
I've got a shure sm57 plugged into my Mackie Onyx Blackjack.
The Blackjack is plugged in via usb to my mac.
I went to system preferences > sound > input and selected the Blackjack as the input.
I went to garageband prefs > audio/midi and selected Audio Output: system setting, Audio Input: Blackjack
On the real instrument track, I selected Input Source: Mono 1 (Onyx Blackjack). When that didn't work, I selected Input Source: Stereo 1/2 (Onyx Blackjack).

I've still got nothing. Nothing is being recorded when I press record in garageband and talk into the sm57. I've fiddled with the Blackjack and pressed all of the buttons and turned all of the knobs, but still nothing.
The power light on the Blackjack is green, phantom power is off (the shure sm57 doesn't need it), and no matter how loud I speak into the sm57, I can't get the SIG/OL light to go on.
What am I doing wrong?? What am I missing here??

 

[mjbphotos]

Plug a set a headphones into the Onyx jack - can you hear the mic?

 

[mdainsd]

If you cant get the sig/ol led to light on the Onyx, then the problem is more than likley, 1) settings on the Onyx (but its dirt simple), 2)bad mic cable or 3) bad mic. If you arent getting a signal led the computer has nothing to work with so no amount of dicking around with its settings will get it right.