Like others have mentioned, it can be like a stim at times.
I have a tendency to loop fragments over and over again.
I can perceive the tones from things like motors and like to harmonize with it with major 3rds, Perfect 4ths, and Perfect 5ths. It's especially fun if the motor is moving and you have to go along with the Doppler effect.
For some odd reason I have nearly perfect singing pitch in falsetto but not nearly as much so in regular singing voice.
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We seldom realize, for example, that our most private thoughts and emotions are not actually our own. For we think in terms of languages and images which we did not invent, but which were given to us by our society - Alan Watts