Check your stutter if it's in your voice or mind. 1. Think of a word you get blocks on. 2. Now try speaking that word in your mind. 3. If you're unable to speak it fluently even in your mind, the stutter is only in your subconscious mind. I noticed that when I am half asleep and someone asks me something, I reply almost fluently. But when I am fully conscious and say a word even in my mind, It is hard.