I'm sure the doctors have looked at medication you are/have been taking and infections. You might consider a strict Autoimmune Protocol (AIP) diet. I started the day they had to stop my medication because of possible hearing loss/tinnitus. It is a very strict paleo diet, the first 30 days were very tough. I felt like I was dying, but it has helped my inflammation. Autoimmune conditions can affect hearing, as well as, metabolic disorders. There are two very good online communities, The Meyers Way and The Paleo Mom. One is an MD and the other an a scientist. I thought if inflammation is in the ear, it can't hurt to lower inflammation. I cannot take steroids because of severe side effects, so the diet/lifestyle changes were the way to go for me.