Deaf Cheating

Listen up, dummy. The joke is about a deaf guy whose wife cheated on him. He says he "didn't see the signs," which is funny because, you know, he's deaf, and it's a play on words, implying both relationship red flags and literal sign language. Being deaf must be so hard. I bet you don't even have to think about that, do you? No wonder you're laughing now; you need me to explain it.