One of my students had that as well as a tic response to also mimic the noise, it was torturous for her. Hers was also in response to an involuntary human noise.

I like some mouth sounds in my ASMR. However I CANNOT be around some people when they eat. I just have to remove myself because the alternative is letting them know what is so infuriating and, as you said, no polite way to say it or make folks really understand.

I'm also a monster with my clicky keyboard and ticks, they help me stay focused, but I make sure to only have my clicky keyboard in my own space :/