I've actually got the same problem and I went to ENT to see what's wrong. He asked for blood test, CT scan and allergy test. I got them all done and there wasn't a tumor or allergy . At the end he found that I've got what's called Epstein Barr Virus(EBV). I'm on 4 different vitamins and a weekly needle for two months time. Hope I'll heal soon as the tinnitus is unbearable especially at night.