Echolalia is when autistic people repeat noises, phrases or words that that they hear. My severely autistic brother does it all the time. Its the main part of his speech. He doesn't say it TO people because he doesn't have conversations, he just repeats things others have said all day long.
I never thought I did it because I don't repeat what people say when they are talking to me but I noticed that I do do it with sounds. If a car horn beeps, I'll say "beep", the same when a dog barks or a cat meows. I don't do it for every sound, but I definitely do it.
Any other people here have echolalia?