Hi
I have had tinnitus for many years as a result of ear/sinus infections when I was a kid.
Unfortunately, I have found it has gradually worsened over the years especially with my increased flying schedule and the pressure on my sinus/ear drums.
My GP has been very helpful over the years with suggesting surgery on my sinuses (something I do not recommend) and 'remedies' when the noise has been particularly bad, including 'white noise' boxes, etc... But even he has admitted 'the damage was done a long time ago' and maybe I should consider cutting down on the amount of flying I do (must suggest that to my employers).
Sorry I can't be more positive and every person is different!
Kaz