[genewitch]

this immediately struck me as a possible example of "The Hum"[0], although that is said to "peak at around 40hz"

[0] https://en.wikipedia.org/wiki/The_Hum

And on the main topic, i occasionally have ringing ears, and about 90% of the time i know why (usually a loud engine that i wasn't wearing protection near), but 10% of the time, like during a quiet weekend at home - it appears out of nowhere. I am not sure what my frequency is, but it's well over 1khz.