Rob: Hello and [bad word] to the English We Speak. My name is Rob.

Helen: And hello, my name is Helen.

Rob: Hold on Helen, hold on. We can't hear you properly. I think your microphone is playing up.

Helen: Playing up? 

Rob: Sorry, I didn't quite catch that. 

Helen: Let me just push this button. There! Hello. Now, you said the microphone was playing up?

Rob: That's right. It wasn't working properly. If something isn't working as it should be, we sometimes say it's playing up.

Helen: Up – not down?

Rob: Nope. Playing down is a different expression that means something totally different. 

Helen: OK. So as the picture on my TV at home is flickering, I can say my TV is playing up?

Rob: Exactly. Let's hear about some other things that are playing up…

I don't think I'll be able to give you a lift to work today, my car's been playing up.
My phone keeps playing up. Every time I dial a number, it just switches itself off.

Helen: That sounds like my phone! So if something isn't doing what is should do then it's misbehaving?

Rob: Ha Ha! Well, you could say that. It's just like people. When they misbehave we can say they're playing up. Like this…

Sorry but I'm going to be late. The children have been playing up and I've still got so much to do.

Helen: Children are very good at playing up; it's usually because they want attention.

Rob: Now, Helen, could I have your attention now please because playing up is also something you can say to describe a part of your body that's not working properly.

Ow! I'm going to have to lie down; my back's playing up again.
Count me out of this weekend's football match; my leg's playing up so I need to rest it.

Helen: So it seems playing up refers to anything that's not working or behaving as it should. Now Rob, my leg's also been playing up so I wonder if you could give me a lift home in your car?

Rob: No way - oh it looks like my microphone's playing up now!

Helen: No Rob, it's you who's playing up - now switch it back on! 

Rob: Oh, oh OK then Helen! 

Helen: Let's go then. Bye!

Rob: Bye.