Up until I was 30, client calls were the worst thing for me and I would do anything to avoid them. I would procrastinate badly and ended up in some unpleasant situations that could have been avoided. Somehow everything just got easier - I changed companies and became a father. The internal anxiety over my speech quieted. Now I don't hesitate to call anyone and the stutter rarely comes up over the phone - it can still in person as a block, but doesn't get in the way. I'm still a little socially awkward, but that's likely on me and not as a result of my stutter.