I can open my eustachian tubes by flexing some muscles at the back of my jaw. I’m pretty sure that’s what’s happening because I hear a “click” or “snap” sound in my ears and the pressure in my ears equalizes with that in my mouth.
I know some people can’t do this because they complain about their ears hurting on airplanes and such.
Can most people do this, or is it uncommon? Can you do it?