Hi KKL;
While I usually associate most cases of tinnitus with hearing loss, being just 4 mos. post op, the brain is still probably pretty traumatized over the entire ordeal and there may be edema yet.
Tinnitus can do what it wants when it wants. Theory is the brain is searching for a good auditory signal from the periphery ( the ear ), and is not getting it so searches for the ear itself. Somewhat akin to "Phantom Limb Syndrome".
I had no tinnitus for several years after translab, however. Of course, that particular op is a complete hearing loss.
As I'm NF-2, the other side has tinnitus also and my head is a veritable orchestra of steady, high pitched noise mixed with fluctuating tones which come and go and increase, then decrease in intensity.
I enjoy the crickets the most. It's like being on a camping trip in my own bed.