I have had similar experiences. When I am drinking I can not shut up. It's fluent as ever, talking on the phone it gets REALLY BAD. I think mostly because I can't see the other person. I don't know how they are reacting or if their on the other end laughing. When you mix all of that in while trying to talk. I feel is what makes it worse while speaking on the phone. I try not to pay bills or nothing through the phone. ALOT of automated systems asks you to say something like an account number for example. Well that's easy for a normal person. For someone who stutters, not so easy. So a simple phone call can turn into a nightmare.