TV Advert tricks

I have recently become aware of something that seems to be a very sneaky trick by advertisers on the TV to get your attention.

I specifically notice this trick on the recent NatWest Bank advert playing here in the UK where a man is buying Euros for his trip to a wedding in Italy.

What's the trick? The almost imperceptible sound of a mobile phone ringing in the background. Keep in mind that the audio track on the advert has background music, the sound of a voiceover artists and the two actors all in the mix at various times......and that mobile phone.

The most annoying thing is that it works! On more than one occasion I have looked up from whatever I was doing to see if it was my mobile (even though I have a different ring tone set!)

I 'think' I have heard the same trick on other adverts too but have not noted what they were in the same way as the NatWest one.

Has any one else become aware of this?