This is a pun on the word 'noise', which can mean 'sound' or 'interference'. In the first sense, the sentence is a simple question about whether the French are bad at learning foreign languages. In the second sense, the sentence suggests that the French are actually good at learning foreign languages, but only if there is noise. This could be interpreted in a number of ways, but one possibility is that the French are able to learn foreign languages more easily if they are immersed in the language, rather than studying it in a classroom setting.