This is a pretty clever video, or should I say, scale. Each time you play this, the recorded audio seems different in pitch, going higher and higher. Go ahead, play it once, then play it again.
Can you say “weird”?
As a music major, I happen to know how this works. This is a Discrete Shepard scale in which multiple tones are played at the same time (low and high). Since all of them go up, your ear gets used to the pattern and expects it to keep going higher; which is why it seems to do so when you play it again.
In reality, you are actually hearing the same thing over and over again. Don’t believe me? Just play the first few seconds of the clip, pause it, then play it again from the beginning.
Sure enough, they are the same tones.