You don't have to worry about being a PITA on this forum Tom, we are all delighted to help.?
Did you say you already have a another QCX?
If not, I am in the Newmarket UK area and can easily check your ATmega328P on one of my radios.
Then at least you will have eliminated one element of the puzzle.
73s Ted
2E0THH
Ted 2E0THH