We know that usually sound that is perceptible by humans has frequencies from about 20 Hz to 20,000 Hz, but as the title said, I can still hear the sound of the outputs of the following code:

```
(* The following sound won't cause discomfort… I think. *)
Play[Sin[1000000 2 Pi t], {t, 0, 1}, SampleRate -> 10000000]

```

After asking some of my friends to hear them, I'm sure I don't have clairaudience. I think it's probably not the fault of *Mathematica*, it might be an issue for loudspeaker, but I failed to find an answer by myself and I think it's worth posting a question for this.