Had it for decades after an ear disease when I was a teenager, just naturally filtered it out until someone mentioned tinitus then I’d notice it again! I recently had a big volume increase after covid, saw an NHS audiologist but they couldn’t do much other than give advice on how to ignore it and refer to ENT but they’re all swamped so might be ages.

Am trying a few things to help with potential sinus issues to see if that helps, nasal douching, avoiding dairy, beconaise inhaler at times and some eustacian massages from YouTube.

There are apps that include a filter which you set at freq of the tinitus then it’ll play noise or music with that filtered out. Didn’t make any difference for me but some swear by them, tinnitus aid was one I tried.