I've seen this called Somatosensory Tinnitus [0], and it's what I have as well. Stretching my neck & clearing my ears of wax pretty much resolves it every time, or at least helps a lot.

I only have it on the left side, and my TMJ lines up marginally worse on that side, so it's probably related.

[0] https://www.sciencedirect.com/science/article/pii/S180759322...