The UFlyMike product enables an external source to provide music playback into the QC2 headphones without priority muting or control of received aircraft radio, air-traffic control directions or cockpit intercom communications. This design may allow music to mask critical cockpit communications.
Bose also does not recommend this type of usage with the QC2 headphones because no incoming audio will be heard with a discharged or improperly installed battery. This shortcoming could result in the potential of missed air-traffic control communications while piloting an aircraft.
I have to agree with Bose on this one, don't get one of these gimmick gizmos, get a real airline headset.
I've seen these hotwired plugs so folks can play their DVD audio over the interphone, one wrong button push and you're transmitting 'Top Gun' on guard. I'm not big on watching movies in the cockpit anyway but have seen pilots set a notebook up in front of the thottles so everybody can see the screen, but not the EICAS. I rode on a US Air jumpseat a while back and one of the pilots brought computer speakers to put on the glareshield to have some mood music for cruise. All you have to do is catch one of the wires on a throttle or fuel cutoff as you get out of the seat to hit the head. They were playing CDB so maybe it was a former Piedmont crew.