A former boss of mine took off to Everest for a month leaving me (a 22 year old, at the time) in charge of the office. I was out to dinner with my now wife when I got a call from a very long phone number I didn't recognize, so I ignored it. I then got another one right after, and picked it up. It was my boss, he needed me to log into his personal email to grab a phone number for the medical insurance he purchased for the trip, because he had been vomiting for days due to altitude sickness, and needed a medical evacuation.

That was the most stressfully hard to use phone call I've ever had. The delay was nearly 10 seconds, and eventually I just said I was only going to speak yes or no, if he needed a longer answer he needed to shut up. And that worked. We no longer talked over eachother.