Apple are blocking off other vendor’s cables via the use of codes/firmware so that you must purchase a genuine Apple product. Therefore we recommend only using Apple products. The following Youtube video of an Apple user that also explains this; https://www.youtube.com/watch?v=bNKK22PclgM
Having said that, here are the required cable(s):
http://store.apple.com/uk/product/MD821ZM/A/lightning-to-usb-camera-adapter
For more information please read here: https://ifi-audio.com/home/computer-audio-tutorial/apple/
