Basically what this is saying is that if your radio is loud enough for anyone else to hear and that person finds it annoying, you are creating a nuisance and in that instance you're breaking the law.
Often times when a cat is purring, it is adorable. When you're listening to the loudest car in the world it can become more annoying than cute and adorable. The Guinness Book of World Record's has a new record holder for the loudest cat...