This is a good Digi-Key article on suppressing acoustic noise in switched-mode power supplies. Interesting point, a ceramic capacitor deforms under voltage swings and can act like a tiny piezo speaker when being charged and discharged!
20200417/https://www.digikey.com/en/articles/suppressing-acoustic-noise-in-switched-mode-power-supplies
This is another good article on different types of switched-mode power supply control architectures and the Torex HiSAT-COT in particular.
20200417/https://www.digikey.com/en/articles/torex-hisat-cot-control-architecture-tutorial