what are the functions of music in twelfth night?

Answer 1

Music is the buffer against the world outside. "Twelfth Night" begins with Orsino saying,

"If music be the food of love, play on;
Give me excess of it, that, surfeiting,
The appetite may sicken, and so die.
That strain again! it had a dying fall:"

It is music that cloys, that sickens, it is music that is not real, or at least is not intended to heal.

The last scene of the play is the fool/clown singing:

"When that I was and a little tiny boy,
With hey, ho, the wind and the rain,
A foolish thing was but a toy,
For the rain it raineth every day.
But when I came to man's estate,
With hey, ho, & c.
'Gainst knaves and thieves men shut their gate,
For the rain, & c.
But when I came, alas! to wive,
With hey, ho, & c.
By swaggering could I never thrive,
For the rain, & c.
But when I came unto my beds,
With hey, ho, & c.
With toss-pots still had drunken heads,
For the rain, & c.
A great while ago the world begun,
With hey, ho, & c.
But that's all one, our play is done,
And we'll strive to please you every day."

"The rain rained every day" even in the play. Music is the only barrier against death in the outside world.