What were the most surprising things for deaf people who gained hearing later on in life?

My cousin was born deaf and went through an operation to recover part of his hearing when he was 12.

He sometimes uses hearing aids, but he can get by without them in general.

His family had a bunny, tu-poo. Of course, he'd learned about cows mooing, cats meowing, all the usual farmyard animals

before he'd had his surgery. He was very shocked when he came home and greeted his bunny

that it made no sound. It took the longest time for him to understand that bunnies are pretty

quiet animals in general. He explained that he thought all pets were loud.

My old roommate in New York City got implants at, I think, he was 25 or 26.

He was shocked that the radiators in the house didn't make noise.

He could feel them, and was absolutely sure, given their shaking and vibrating from time

to time, that they were going to be quite noisy. On the flip side, he was deeply annoyed by the buzz of fluorescent lighting, which he did not expect to make that much noise. I had a child friend that gained hearing, and she didn't realize you could control the volume of your voice. So, when I whispered to her, she said, hang on, I think I need to adjust my hearing aid.

At first I just thought, oh, it mustn't be working until I realized what was going on.

She whispered to me for about two weeks solid just to practice. Yes, she also practiced shouting,

but we did that in secluded woodlands. My friend got his hearing at age six.

He swears to this day that he thought flowers would make some sort of noise and that's what

attracted bees.

Nernroot makes a sound to attract adventurers, actually.

I went deaf due to illness, probably around the age of four months.

Got my hearing back at around eight years old through surgery.

I used to think traffic lights should make a noise. Street signs too. Like when a stop sign has a

blinking light for added visibility, I think that's actually where I got the idea in my head.

They're trying to get your attention, right? So of course they must put sirens in all the traffic

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