The Alesis IO Dock is a great product for iPad musicians – this small hack makes it even greater. It overcomes one limitation of the IO Dock: You can’t simply hook it to a USB hub. So I decided to build in an additional hub – which allows me to hook up additional class-compliant interfaces like my M-Audio Axiom master keyboard, and power them via the hub.
Yes, it works. No, it hasn’t been thoroughly tested yet. So try at your own risk.

Full Tutorial (nice)