[rhubarbcustard]

A non-linear loss should not be an issue for any modern hearing aid, they are designed specifically to deal with that. I've never seen an audiogram with a complete flat (linear) loss, I'm sure some have it but its not common.

I have a severe sensorineural loss in both ears and wears hearing aids with a lot of success. My loss was the result of some unknown illness when I was younger - a loss resulting from illness or drug reaction tend to present randomly across the frequencies, whereas an age-related loss is almost always a "ski slope" loss, which means the high frequencies are mostly lost and the lowers are mostly fine.

Your experience is very common with new hearing aid users. The aids are able to increase volume at specific frequencies as defined by your hearing test(s) and the other features of the aid, e.g. noise reduction and compression are able to give a great quality of sound. The problem is usually in the person's ability to comprehend these new sounds, i.e. their brain, not their ears. A person with a hearing loss typically takes seven years to try out hearing aids, in those years their brain has got used to not hearing certain frequencies and sounds altogether and it can take time and training to get that ability back.

There is not really a great set of tools for brain training part of the hearing problem at the moment, in my opinion its badly overlooked by the hearing industry.

This is a very interesting book: https://www.amazon.co.uk/gp/product/0262045869