They are talking through a complete hole in their head

This one comes from a Wall Street Journal article about Scotch Whisky:  “Whoever is saying that is talking through a complete hole in their head.”  This is a mashup of “needing something like a hole in the head” (to have absolutely no need for something) and probably “talking through (one’s) hat” (saying foolish things, or bluffing, boasting).  “Off the top of (one’s) head” (from memory; without much careful consideration) might be in the mix, but since the word “through” is used I would bet on the former.  Another thanks to frequent malaphor contributor Barry Eigen for spotting this one!