For me I'll only have trouble with "t" and "c" sounds when I'm speaking to myself, but it's really minor and unnoticeable. And I might stumble over some words when reading aloud to myself. Whenever I stutter around people it's not being able to pronounce the first sound in a word when I'm talking, it's as if there's a mental block and is followed by a few twitches and repeating that sound. My stuttering starts going away when I start talking with more and more people, but it's been getting worse lately because I work behind the scenes at a national park, so not a lot of people interaction.