Sheila & B. Devotion - King Of The World (1980). There's an incident during the performance and for those of you who don't understand French associate Luc has translated what is said for us. Thank you Luc:

Guy Lux: "Well… all this is not grave. This will give us the opportunity to start again, my little Sheila. Having said that, well of course it is a…" [Sheila seizes the microphone]
Sheila: "Hello! How are you? Guy will explain you that we are live broadcast, that these are the hazards of live broadcasting. We will do as if we haven’t seen us before and start again from the beginning!"
G.L.: "Beforehand we should maybe know if the technique is ready? Yes! I take the opportunity anyway because, of course, you can think… Ah! bah!" [Music starts]
[At the end of the performance]
G.L.: "Thank you. I am going to nevertheless add a small word [repeated twice]. It is true – you noticed it – that this song was presented on tape. It is also true that it happens… – moreover she hadn’t any microphone, Sheila – it is true that it happens in certain songs that, when there is an enormous movement – this is the case of this song – well the tape is required. The tape broke, anyway that proves that it is absolute live broadcasting. Because otherwise, if it would be recorded, you wouldn’t have seen this incident! Thank you Sheila, see you soon."