I just bought 6 days ago a new MBP 16'' M1 Pro 16GPU and I'm getting this annoying sound from time to time while watching youtube or listening to something else, I was also able to reproduce this issue several times by doing this.
open a browser (Firefox, Safari or Chrome) and play any youtube video (and try to lower the volume a bit), then open "Audio MIDI Device" select "Macbook Pro Speakers" then select "Configure Speakers" and finally click on the Test Icon (left or right), and every time the test audio ends the annoying sound will be there.
This is an expensive machine and do not think it should have this kind of issue.I'm thinking about returning it.
macbookpro16-2021
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