Had tinnitus years ago that I couldnt get rid of, turns out it was related to sciatic issues I was having. Changed my gym routine up a bit and started doing daily stretches focused on my lower back and both eventually got better. Didnt really link the 2 until a couple times my tinnitus would come back before my back would start acting up so these days it can be an early warning sign for me to take it easy.
I know there are other more common issues that cause tinnitus but if you have any kind of back/neck pain would focus on that and see if it helps. When my tinnitus was a problem the only thing that actually helped were some sound therapy videos I found on youtube, but it was only temporary.