I think "sonic errors" nails it. I also think many usage errors, especially in spoken English, stem from the fact that (alert, generalization ahead), many people don't read much and if they do read they're reading attrociously written prose. Another of my pet peeves (yes, I am often peevish ), is idiom butchery. Naturally, I can't think of a good one just now, but I'm sure y'all know just what I mean!