Ive been wondering about my hearing issues lately, too. I have occasional "bursts" of tinnitus, i assume from my hypertension, but ive also been looking for answers regarding a weirder phenomenon ive started noticing in recent years. Hyperacusis seems to be the closest word for it, but for me it manifests as isolated spurious noises seeming louder than they are. It sounds like someone turned up the gain on my ears for a split second before the sound occured, and then right after, returned it to its normal volume envelope. Its startling and unsettling, but i dont have the "conversational voices are too loud" type of symptom. Anything similar for you?