@Gabriel
Hey there, what you described with the frequency distortion is basically exactly what I have! I did a frequency sweep and there's a substantial amount of damage around 1k-1.5k hz. And some sort of buzzing that attaches itself to low frequencies (130-200 hz). What's odd is if I turn up the tone more loudly the distortion disappears and it becomes normal again. Which makes me think synaptic damage.
Did things ever get better for you? A lot of music I've now come to realize sounds completely distorted and wrong as a result, and it's completely destroyed me. Other songs completely normal which is I'm assuming because the tones in those songs remained undamaged.
I'm one month in and there's been no improvement.
Also the ocean, traffic, and road noise inside the car has kind of this white noise layer on top of them. Im not sure if this is just distortion or hyperacusis because it makes everything sound so loud to my ears. I can't stand the heater now because it's like walking next to a lawn mower - it really does sound that much louder. Or maybe the distorted frequencies are causing this extra sound layer to appear?
And then there's my 2 reactive tones (the low siren sound and the high pitched whistle that like to respond to pretty much everything)...god my ears are a mess.