Fancy a quickie?
My son does this weird thing when he's immersed in play. Basically he narrates whatever he's doing - but with a strangely high-pitched voice. He'll also get very sloppy with his speech and pretty much just squeak along in gibberish. Sometimes he might interject with a bossy low-tone - but not today.
And to balance it out here's my daughter "proving" that she can dance without music, "better than you." Truth be told any independent sound would have caused her to try and move along with the beat and therefore to violently thrash around on the floor.