Earlier quoted context omitted.
Mine sounds exactly the same! I usually describe it as the sound of "brightness" and it does feel like something coming from inside my head, instead of from the outside word. As many people, I cope with mine by just ignoring it, most of the time. Sleeping has been hard though, since I can remember. Today I resort to some kind of color noise, such as a fan, air conditioner, or white noise apps (brown noise works best)…
About 4 years ago I was listening to a podcast. One host was explaining to the other that he had tinnitus, and what that meant. I still remember how shocked I was when I heard the tinnitus host was in the minority of the population. Never knew what tinnitus was, but had assumed everyone heard a low buzzing noise. I always thought a low buzzing noise was what silence meant.
As far as I know, many people who don't have tinnitus are able to experience such auditory hallucinations in a sensory deprivation tank or similar.
If that assumption is right then the difference between tinnitus sufferers and others is of degree: the level of background sensory input at which consciousness of such hallucinations might kick-in.
Hence, tinnitus or not, lower auditory input tends to lead to greater likelihood of auditory hallucination.