Dang! My first negative - unfortunately the E17 can't be used with the iPad and the camera connection kit. "The attached device uses too much power" or something to that effect. I tried using a dual-powered USB to microUSB cable and alas I still get the same error message. Also tried using the USB DAC through the E9, hoping its external power supply might help, but no go. Bummer.... ;(
Guess I have a reason to hold on to my Pico - it works perfectly going iPad --> CCK --> Pico microUSB --> Pico headphone out, choosing USB Audio Device from the list of outputs on the iPad. Sigh.... wonder if it's something that can be fixed via a firmware update or if we need a special microUSB cable that ensures the E17 doesn't try to draw power from the iPad?
Have you tried turning off USB charging on the E17?