Sometimes you hear a xylophone
deep in the forest and you know
that things are just not right.

The opening lines to the poem You Don't Know Me, by James Tate.
Later in the poem the narrator gets into a colloquy with a song, which ends this way:

There's a hole in my head, I said,
I was hoping you would help me fill.
What do you take me for, skillet biscuits?
Perhaps. But you are also the forest song
which is long and deep and clear.
I exist but I have no purpose, the song said,
but I'll pour some cool water over you
that you will not soon forget.