I was walking along one day and I noticed up ahead this guy who had a banana in his ear. So I said, "Hey Mister - You've got a banana in your ear." He kept walking, so I said a little louder, "Hey Mister - You've got a banana in your ear." He just kept walking, so I called out as loud as I could, "Hey Mister! You've got a banana in your ear!" Still, he just kept walking. So I ran up ahead of him and turned around and put up my hands so he would stop and shouted as loud as I could, "HEY MISTER! YOU'VE GOT A BANANA IN YOUR EAR!" He stopped and looked at me and said, "Sorry, I can't hear you sonny, I've got a banana in my ear."
I remember that joke from my childhood (that's in the 1950's - way before Bert and Ernie did it) and my Mom laughed every time she heard it.