You might be onto something there.

I'm a fellow smoker. My hissing (gas escaping with white noise with
occasional high pitched thingy) tinnitus is worse when I'm in bed
trying to sleep (in spite of not sleeping much the night before - 2
hours or so - last night I went to bed at 1 a.m. and was still awake
at 4 a.m.)

I don't sleep in bed any more (my wife's not keen on smoking in the
bedroom). I wonder whether it's connected.

Likewise, when I'm at work (such as right now) it's very loud. We
can't smoke in the office and have to go outside to smoke. But it's at
work and in bed when I tend to notice it the most. When I go to the
pub at lunchtime, where I can catch up on my beer and cigarettes, I
rarely even notice the tinnitus.

You could very well be onto something here, old chap!  You never know
- there could be a real medical reason for it (after all, the ears,
throat, nose etc are all connected). Problem is, it's the sort of
"research" that few doctors would be willing to advocate, and few
journals would be willing to publish, because smoking clearly has
negative side-effects eg lung cancer.  So it's up to poor sods like
you and me to have to carry out our own research.

Good luck!