Not all dissimilar to synthetic clapping, synthetic birds, synthetic finger popping, etc.
It is the sound of human whistling created solely by synthesizer hardware or computer software synthesis. Most frequently heard on TV commercials for various & sundry household products; especiall.

No actual lips are injured or otherwise harmed when synthetic whistling is employed.
The Take Control margarine advertisement from the turn of the century had this horrid synthetic whistling in it. Made me want to throw a large tub of frozen Gold & Soft margarine right through my TV set's boob tube and then suck up all of the glass with a bagged upright vaccume cleaner so that the cat doesn't cut her paws on it! :-(
by Telephony May 8, 2015
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