Dunno about tinnitus - I've had it for decades; it went along with my loss of high frequencies and I've worn hearing aids for over 20 years, and sleep has not been an issue for most of that time, but good sleep can help with many an ailment.
Tinnitus
I read this article and i thought it may be interesting for those affected by it.
https://www.sciencealert.com/tinnitus-seems-to-be-somehow-linked-to-a-crucial-bodily-function