To be clear, you only want to leave because you're frustrated with a few calls? Not because your managers have approached you about doing a better job? I get it. Phone calls can be the worst. If you feel the need to quit then do what you need to do. But it sounds like it's not a big concern for your managers. Or your coworkers. Maybe no one mentioned it because it's not a big deal to them. Maybe they don't even notice. You may be surprised how completely involved some people are with themselves lol You should be proud of yourself, working in one of the most challenging jobs for someone who stutters. You are actively working on your speech every day at work. That's more than most people.