What a load of crap.
First off, those "boxes" that distribute media are covered by cases that are secured by screws. There's no "wiggling" and such to get a cover off.
Also, the media is stand alone, and is not connected to the flight system...saying he can "hack" into flight controls via the media system is like saying you can "hack" an ATM by connecting to a light socket on the ATM's cabinet.