Good point, our hearing can and does vary depending on our inflammation status.
To be anatomically correct, our ears directly connect to our throat (not the sinuses) by the eustachian tube. But if your sinuses are swollen or inflamed, the eustachian tube probably will also be affected. Normally this tube is open to the air in your throat, but if it swells shut, or is filled with fluid, because of inflammation from a head cold or allergic reaction, your hearing will be affected.
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