Oooh that happens to me too. I don't have ADHD (or at least I think I don't) but my hearing is kind of shite so I would hear "Whet dine wizzit?" and then ask what and in the meantime my brain realizes what the actual words were supposed to be and then I answer.
Yeah I do this too. No ADHD, but i think once I already asked what, my brai actually process it or when they start the question I confirm I heard right and reply.
Actually, this is may be Auditory Processing Disorder that is strongly linked to ADHD, where you take longer to process what people say and then seem like an idiot for not responding or responding later, or, like me, anticipate what you were going to say, guess wrong, and respond with the wrong answer. I didn't know I had it until I went for a hearing test because, well, I couldn't hear/respond well, and turns out, it's not my ears, it's my BRAIN. Thanks, brain.
Oh no.