Truly Odd

Shhh, don't speak.
Hear that?
No?
Yes?
A little bit?
That high pitched ringing.
It makes you want to cover your ears.
But you still hear it.
And the odd thing is,
Nothing is making any sound.
And you only hear it,
Once in a while.
And no one else can.
Truly odd,
Isn't it?