If your db of moans are higher than 120db, your moan could transfer to a deadly moan
Just imagine, you and your husband are making love on the bed, and your husband just passed out because your deadly moan. You called 911 quickly, and just realized your husband is severely paralyzed because of your moan.
You make a choice, you're gonna take care of him in rest of your life. And 10 years passed, your husband looks like still doesn't has any chance to take up. 30 years passed, he make it through to the 100 years old, and you realized you didn't getting older these years, for a unknow reason
And quickly, 100 years passed, you both still didn't pass away, you just realized your moan in that time just destroyed a chain of ages, so it means you two can theoretically live for infinite years, which means eternally life.
And eventually, your husband woke up, with the scene of future. He curiously asked you "Where and i and how many years passed?", you didn't answer it, just smiled, you both is gonna rebuild the human civilization.