Belated welcome to you, elistar. I have delayed this
deliberately, 'cause I wanted to have the answer for you.
But alas, my sensibilities are now out of whack--I couldn't
find it on the 'net or the library resources.
The closest I came may or may not be a hint: a ref. to
baseball, where the next batter takes a whack. If whack in this sense indicates doing things in a certain order, then
out of whack would mean out of order, or wrong.