I don't hear any vocal effects when connecting my mic via an external I/O unit for my iPad. What's wrong?
There's many different ways that external I/O units route audio within iPads. To get things to work with Voice Rack FX or VoiceJam Studio, you may need to use AudioBus.
If you activate Voice Rack FX or VoiceJam Studio and don't hear any effects/loop output from your app, you may need to add a "System Input" and "System Output" module in AudioBus to direct the audio in and out of your I/O unit.
See the AudioBus site for support and forum discussion: http://audiob.us/