May 20, 2007 05:14 pm Hello,
I don't use audacity but as long as you are getting sound into your mixer it could be one of three things.
1.Check all your cables
2. Check that your UCA sound interface is selected as the default sound card. Do this by going into control panel, sounds.
3. Check that the recording input on the channel that you're using in audacity is set to receive the UCA. You should be able to adjust this on the indivudual track itself.
I don't use Audacity but this should help.
Good luck,
Nathan