They only last about 30 seconds - but they're some of the most familiar things on TV, and when theme tunes change some viewers can get pretty upset.
That's what has happened to Dr Who, which changed its theme tune to mark the arrival of the eleventh time lord.
Doctor Who bosses have added an extra trumpet line to the hit TV show's theme tune, and not all fans are happy about it.
In fact, 70 people were so upset about it they complained to the BBC!
Home~RS~q~RS~~RS~z~RS~30~RS~)
