Not really as a tinnitus entity. Some triggers are known and some triggers happen for just about everyone. Tinnitus has many anatomy and physiology associations.
Yes. Tinnitus will resolved in 100% if a twisted nerve between C5 and C6 is fixed, not so for many other problems. There are so many diseases and conditions that associate to tinnitus. Tinnitus can have association to 97% of biology from the waist up and the higher the biology gone wrong often more so.
It's different diseases with one same symptom - something gone wrong where the brain isn't happy.
If a dish is dropped it might break, but never the same way twice as there's too many variables. We are basically dishes made of the same stuff.
Taking about tinnitus is as complicated as a discussion of the universe or even politics, or most anything else. Tinnitus has many variables, but the brain says so what, I'm not picky.