ADK Mega board is causing severe errors on Galaxy S3

First thing I did when I received my new Mega ADK v3 board: I plugged the board into a 9VDV supply, and plugged in my Galaxy S3 via USB to see if it would charge the phone. It charges, but the board is causing crazy electronic interference that is messing up all touch movements on the phone. Phone is unusable when plugged in this way. Is this something that a ferrite choke on the USB cable would correct, or is it more serious? --David