Thanks for the tip, but it still isn't working after I uninstalled Gearbox and installed Pod Farm. In fact, I still have the very same problem.
One strange thing though: just like Gearbox, Pod Farm states that the UX2 is connected to the software. On startup, it even automatically detects which of the two inputs I plug the microphone or guitar into. But no sound, and the dials aren't budging.