I've had the same problem in a milder way for years from the other direction, whenever I go up to a customer service person to ask for help. Try rehearsing the *word order* in your mind of what you want to say to the customer. I find if I do this, it doesn't matter how nervous I am, or how much the word intonation or diction in my silent thought processes gets put through the cuisinart. My speech comes out clearly, nonetheless.