Uninformed guess: "The master [public address system] power button [located] up by [seat] 1L kept getting pushed so it would shut off all the IFE [(inflight entertainment)]"
This makes sense, because for safety reasons all the entertainment is paused when they use the public address system.
I think "master power button" probably more clearly means some sort of master control switch for in-seat passenger accessory power, since it's described as shutting off all in-flight entertainment AND seat power. The sort of thing you're supposed to press during takeoff and landing, not during announcements
You're right, I forgot because I have just used my phone the last few years. Now I remember I always found it incredibly annoying because I'd miss part of the dialogue of what I was watching.
I can't even get passed the first sentence of this. What does any of this mean?