The soundcard in your PC is bypassed when Pod Farm is used with the XT. The XT becomes the soundcard. That means the sound produced by the Pod Farm software is sent over the usb connection to the XT and is played by the XT. In order to hear it you need to connect your monitors (headphones or speakers) to the XT. You won't hear anything from the speakers connected to your PC soundcard because that soundcard is not being used to play the sound.

If you don't have external speakers for your PC that you could simply disconnect from your PC and reconnect to the XT, and if you don't have headphones, then there is one way you can use your PC internal speakers. You can connect the XT headphones output to your PC soundcard input. That way you can force you PC soundcard to receive and play the sound produced by the XT. I don't recoemmend it, but you can do it if you wish. The sound quality will suffer because the XT is a much better soundcard than the one built into your computer. It's kind of like buying a great audio system for your HD TV, and then listening through your tinny little TV speakers anyway.