Funnily enough, just listening to high pitched noises reduces my tinnitus:

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

Ah interesting. I had noticed my tinnitus would get worse when I had been sitting in silence for a while, especially with over-ear headphones to further dampen ambient sounds (ie album ran out and I was so preoccupied with coding I didn't put another on).

Fortunately mine is just at a mild annoyance level so far, but will try your trick.