I think going mute would give you ever bigger anxiety for moments when it's time to talk. I feel for you on this and I hope and pray it gets better for you. Start by practicing everyday just speaking out loud by yourself. When that's super easy and relaxing, throw in looking in the mirror. Then move to recording yourself. And eventually, try to speak to yourself but with 1 trusted person in the room while they're doing something else. You could also try speaking in a very low, slow and quiet voice as well. All of these things have helped me. But man it takes time.