I have I hard time talking loudly, and I tend to mumble when I talk. It's really annoying when people ask me to repeat myself, and having a naturally whispery voice doesn't help at all. People tell me about it all the time, so I can relate.
Another thing that really annoys me is my inability to express my feelings in speech. It's a lot easier for me to write it, but that takes me a while. Things make sense to me in my head and not when I say it or write it. I can never think of what exactly I want to say. Typing this alone took me, like, 15 minutes! :
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