Normally, every sound inputs are available in Option Panel “Select Sound Input”. I know that there is some troubles on the Windows 7, specially with USB Mic or Webcam, but your case is more complexe. Maybe the ASIO driver from the K2 create something wrong.
The new version of Bazik (currently in progress ) used a different way for sound input (and manage USB SoundCard with Multi inputs) but you have to wait for this.
Actually, use an USB microphone can cause problems. If you are interesting, we can work together the next week on this point 🙂