there is treatment for tinnitus, some is more effective than other and it's different for each person, but starting from basic regular earwax removal to even medications, if everything else fails. If you can, just ask your physician about the options you have.
Since your sense of balance is starting to get affected, all this can become just too big of a risk to leave untreated. And, if nothing else, maybe some of the possible treatments actually does help you to not hear that sound,
Wish you all the best,