Our instructor has different categories of questions. He wants to put random questions from each category of questions in a quiz. When he switches categories (e.g. from category A to category B) and clicks "add" to add 1 (or more) questions from the new category (e.g. Category B) to the quiz, Moodle adds those questions from the previously selected category (e.g Cat A). The second time he does this however, it adds random questions from the correct category. This happens every time he switches categories. (See attached screen shots).