United Airlines has updated its contract of carriage to require passengers to use headphones when playing audio or video on personal devices during flights. Travelers who refuse could be removed from the plane or even permanently banned from flying with the airline, reports CBS News. United notes that it will offer customers who forget theirs a free pair of wired earbuds. "Don't worry if you forget your headphones for your flight," the airline states on its website. "If they're available, you can request free earbuds." You'd better hope your device still has a headphone jack... Further reading: Flying Was Already the Worst. Then America Stopped Using Headphones.Read more of this story at Slashdot.