How to Turn Off Silent Mode on an iPhone Dogs will flick their tongue as an appeasement signal but also as a signal they're relaxing. While similar each signal has subtle differences. I will do posts on both. The tongue flick How To Turn Off Vibration When In Silent Mode on Your iPhone How to Change Vibration Settings on an iPhone Spotting Discomfort In Your DogFrom Tongue To Tail McConnell Publishing Inc. Its a trick question, Chattering, when a dogs jaw vibrates and their teeth make a clicking or clacking sound, is a physiological response known as arousal. But heres the key: dog chattering