Hello, As the title asks, I would love it if someone who understood physiology could explain how ETD (specifically blocked) causes tinnitus. I understand the basics, that something (allergies, infection, inflammation, etc.) causes the eustachian tube to become blocked which traps air in the middle ear. The air is absorbed by the epithelia which results in negative pressure in the middle ear (eardrum is pulled inward). How does this cause the ringing in the ear, though? I thought that sound vibrations caused the bones of the middle ear to push into the fluid of the inner ear, resulting in a physical motion of that fluid that is picked up by the cells of the inner ear. How does negative pressure, which should be fairly static, produce enough movement to cause constant stimulation of those cells and result in the incessant ringing of tinnitus? If it's just a space with lower pressure - why does it cause any vibration? I don't understand why ETD-related negative pressure results in anything more than difficulty hearing. Thanks in advance!