I too am having this problem, and have reviewed ALL the forum postings I can find on the subject. Some have asserted that the problem is resolved, but it IS NOT. I have tested ALL the possible settings and configurations, including changing the "Repeat Alert" setting to "Never", but the problem remains. As someone has said, it is not a repeat alert, but rather a "hiccup" or a glitch, where the sound starts, but the fraction of a second later repeats itself, like "B'd-B'ding!" instead of just "B'ding!" My conclusion is that this is a software glitch affecting certain phones, and will need to be fixed with an IOS update.