Not a good idea
I was travelling recently from yyz to dxb on Emirates business class. Shortly after take off, i decided to take out my ipad and headsets and watch Air Accident Investigation ( not a good idea i hear you say).
Having turned my seat to a bed, my eyes started closing and eventually i fell asleep, but still my ipad played on and headsets still on my ears... Suddenly i heard the following " ladies and Gentlemen this is an emergency, the plane will be ditching in the sea etc etc etc..."... Forgetting that i still had the ipad on, and thinking that this was an announcement on my flight, i jumped out of the seat/bed in horror... With a thousand things going through my mind... To my delight, the cabin was dark, everyone was asleep, the plane was still flying normally and the headset was still on my head..
Did i learn anything from this? No, because i still watch the same program when flying