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When I'm on a phone call using my iPhone 5 running iOS 10.3.3, I get the vibration of iMessages in my ear while I'm on the phone. It's irritating to say the least (pun intended.) The recipient can also hear the buzz.
Is there a way to automatically disable all vibrations when on a call? Would the slider on the left-hand side of the phone near the top work? (I'm afraid to try in case it makes it worse.)