I have found the word for the thing I do all the time:
mondegreening.
Many a thing have I misheard only to have W look at me like I’m crazy when I repeat it. Now, at least, I know the word for the condition. And even better, there’s more words in the wikipedia definition – about related words. (Soramimi, and eggcorns, malapropisms and, and mumpsimus. I would color those words in rainbows and sparklies, but that might be a bit too hard on the eyes.)
*swoons with joy*