My tinnitus is still absolutely horrible, almost always there in some fashion, strong nearly every night, and drives me to near-insanity half a dozen times a month.
Just for another perspective.
I don’t think this treatment would help me. My understanding is there are little hairs that pick up sound waves, and excessive noise can destroy those, and you don’t get them back. The brain fills in with the ringing noise. But I don’t see how the stimulation would reset that process.
Ear protection is of course a requirement when playing a drum kit, which is very loud. But when playing viola?
What I've noticed is that the level at which I perceive it is completely linked with my anxiety level. I always ear it but when I'm tired or anxious, it's loud while when I'm really relaxed, it can become very faint.
Unfortunately, I must be a pretty anxious person as it's loud most of the time.
I’ve tried lots and lots of different diets (in the balance-of-foods type) over the years though and nothing really helped or harmed the tinnitus in any noticeable way.
It shouldn't be bothering you at all at this point if you've had it that long.
If you want to keep on suffering, go ahead, or you can learn to live with it.