Do you feel any flexing when you walk on the floor? It sounds like there may be gaps between the tile and what's underneath, and when you walk you force air out and when you step off, it's getting sucked back in as the floor covering returns to it's original position. I think to really solve the problem, you'd have to remove the tile and use level best or some other leveling compound before re-tiling.

Michigan has been having some crazy weather recently with temps all over the place, rain, snow etc. That would make the wood expand and contract and cause little gaps that air can get it. In a wood floor, that could cause squeaking. With a solid surface like tile, the air moving in and out through tiny cracks could cause a hissing sound.

Is this area over a basement or crawlspace so you could
access it from below? If so, you could try putting a couple of screws in from below to hold the subfloor and whatever underlayment is there tight together. Just have someone stand on the area and then drive in some appropriately sized screws. That may be enough to stop the floor from moving and stop the hissing sound.

If not, I would just wait it out until for the winter and see if it goes away on its own when the wood expands in the warmer/wetter summer air. Tearing everything up would be my last resort.