So I bought one today. Along with a Shure SM-57. So i'm trying to run it through Audacity but when I record it has no sound. The sound data is there but there is no sound. I'm not sure if its Audacity or the Fast Track but something is wrong.
Can you hear any sound on your computer at all?
What are you listening out of? It should be from the interface itself.
You'll need to plug speakers or headphones into the Fast Track to hear your recording at playback.
Either that, or go to the Windows Control Panel, go to audio device manager, or whatever it's called, and set the Fast Track to the default record input, but your stock card to the output. This might not be possible with Audacity, and it's not the best way of doing it. Better to listen from the interface, as people already mentioned.