http://geekhack.org/index.php?topic=14290.msg1408316#msg1408316
"
I confirmed the issue you mentioned on Adjustable Keyboard, the keyboard stops working and only replys with error code 'FFEF' instead of keycode after those media keys are pressed.
Hmm, those media keys don't yield a keycode unlike other keys, it may need some special initialization or procedure to get keycode of the keys. we'll need to look for the information among old apple documentations.
"