You are possibly missing a part then. I've had mine for over two years, bought direct from Bose. Maybe they don't include it anymore or that is an Amazon thing, but I use my detachable audio cord, which was included in mine, every commute to plug into the in-seat TV.

The audio jack on the QC35 is on the bottom of the left ear cup. It's smaller than standard though, that's how they get you.

Also to keep it on topic, if they made a Ufly for the QC35 I'd be all over. Most comfortable headphones I've ever had.