To me, it seems that if the nerves/hair cells are damaged, that means they are dead.
Tinnitus can be caused by the brain replacing frequencies lost by hearing damage. So, if your hum is due to the cells that receive low frequencies being dead, I don't see them coming back to life by shaking one's head.
Rather, if your hum is due to something physical, like a nerve being irritated, or pressed on due to swelling, then I can see shaking one's head causing it to change due to momentum. So, shaking your head could be relieving the pressure on a nerve for a second.
I had the same thing. Shaking my head caused it to go away.
I obviously love how you are thinking.
In all honesty, it blows my mind how my low hum behaves some days. Let's call it the quiet days (some days my hum is at 9 all day and I can't do anything somatic to change the intensity).
Today was such a quiet day:
I go upstairs to the most quiet room in the house. The humming is at a 6 (still not quiet ofc but better than 9).
I sit down on the bed and raise my head until my face is almost horizontal > this causes my hum to go up to a 9.
Bringing the head down again lowers it back to a 6.
After being in the dead quiet room for a while (20 minutes) the hum subsides to a 1 (yes, almost completely gone), raising my head until face horizontal brings it to a 4.
Bringing the head down again brings it back to a 1 or even a 0 sometimes.
There is an actual "breaking point" - neck position that brings it from a 4 to a 0, more or less just above a natural sitting position...
When it is at 1 or 0, laying down (on back or either sides, it doesn't matter) ramps it up again to a 4.
Sitting back up after laying down means it is louder again.
After this fun session in our bedroom we went to get food, 10 minute drive in the car. Upon coming back from that short car ride, the buzzing is extremely loud for a good 5 minutes (like a 10 or so), before subsiding back to a 4.
Keep in mind what I said in the beginning, this is a good day, a day where I can manipulate the buzz and it sometimes drops to a 0. Most days are 9/10 and there is nothing I can do to bring it down.
I'm really puzzled about this behavior and I'm inclined to follow your thoughts. I mean if this is really tinnitus caused by low frequency hearing loss, how on earth does it drop to a 0 sometimes or how on earth can I manipulate it like that.
Fact is though that most people have a somatic component to their tinnitus, but my case is almost too extremely somatic.