I'm sure most of you know that, but I'd forgotten.
I didn't realise it but I've been deaf(ish) for a couple of years now, not sometime you can put your finger on, struggling on, using best manners to say, 'You what'?
Then there comes a time when your best mate say's slowly, (so that you can lip read), get your ears tested.
Well, I did, The lady told me after the test, 'Oh yes you need hearing aids, you have classic industrial hearing impairment.
Well, I had them fitted today, a different lady set them up then asked how does it sound?
It sounded awful, all tinny and as if I was shouting.
That's perfectly normal she replied, your brain has forgotten the higher frequencies...