Came here to say I hope this can someday lead to a tinnitus cure :'|
https://www.youtube.com/watch?v=xUZOSg3a1rk
it turns out it's a "phantom limb" problem of hearing - when your high pitch hearing ability decreases, you start to have phantom sounds "fill in the blanks" at the frequency it got worse at
you can test it yourself by generating sine waves and seeing when your hearing becomes worse
https://www.szynalski.com/tone-generator/
mine drops off at 12.5KHz and goes almost completely silent above 16KHz
the tinnitus frequency is about 13Khz!
Trying to listen to quiet noises between 12Khz and 16Khz trained me to be more sensitive to those sounds and to generate less tinnitus
Fortunately mine is just at a mild annoyance level so far, but will try your trick.