Tim Bowen's wise words on idioms have certainly struck the right note with us.
If someone says something that you are very pleased to hear, you can say that it is music to your ears, as in ‘Their offer of help was music to my ears’.
It would be quite a different matter however, should you be required to face the music, as this would mean that you have to accept punishment or criticism for something you have done wrong. If that happens, it's probably better not to make a song and dance about it (complain a lot about something in an annoying and unnecessary way).
Sometimes it's difficult to strike the right note (create a particular mood by the way you speak or behave) but, if you do so, you might touch or strike a chord with someone (produce a particular emotion in them), as in 'Her tale of woe struck a chord with Edward'.
If you change your tune, you change your opinion or attitude, as in 'Is that your dog? You've changed your tune. You always used to hate dogs!’ If you understand the feelings, opinions, or needs of a group of people, you can be said to be in tune with them. A failure to understand such feelings, however, would mean that you were out of tune with them, as in ‘The government is often accused of being out of tune with the aspirations of young people’.
If you dance to someone’s tune, you do what they tell you to do and, in that situation, it's that person who calls the tune (is in control), as in ‘At the moment the money markets are not sure who is in charge and who is calling the tune’.
The expression to the tune of is used to emphasize how large a sum of money is, as in ‘The company is in debt to the tune of £1.2 billion’, and if something goes for a song, it is sold at a very cheap price, as in ‘Many products in the shops are going for a song these days’.