Has anyone used a BT transmitter to connect to the audio outlet of the IFE to transmit audio output to your BT headset?? Something like this, which the yt video is showing how the transmitter is connected to TV, I believe should work on a plane IFE...
https://www.youtube.com/watch?v=z9xMdWuoYig
https://www.youtube.com/watch?v=z9xMdWuoYig