[Zigurd]

I have for a long time used unobtrusive IEMs with Comply tips (MEElectronics, small, black, with a memory wire that guides the headphone wires over and behind the ears). They shut out the world very effectively, and are cheap enough that it's not a tragedy to lose them. I have never had a flight attendant bug me about them.

United is particularly bad about cranking their PA system up into distortion screeching range. It's pure sadism.