Back in my early days of playing bass I lost all the higher frequencies on one ear becaus the earplugs I used for rehearsals (ironically to protect my hearing) had stuffed earwax back into my ear canal and blocked it completely. I noticed it when I could suddenly no longer hear cymbals on one of my ears.
The stuff they sell at pharmacies to flush it out yourself didn't help at all so I had see a specialist and he sucked it out using a long needle attached to some kind of MASSIVE vacuum suction device. The specialist decided to "service" both ears while he was at it. He hit something that hurt really badly in one of my ears. I couldn't open my jaw for three weeks and had to eat soup through a straw. At least I got my hearing back but almost 30 years later that ear still has a weird (but thankfully VERY low level) metallic "humming" from whatever he did in there. He was an old eccentric "mad professor" type ENT specialist who looked thirty years past his retirement age. Imagine an older version of "Doc" from Back to the future. I guess I should have walked right out of there and found someone else...
Still, I think we have established that hearing problem doesn't seem to be the problem here.