I purchased a lot of NES accessories today and one controller has the D-pad reversed. Left goes right, right goes left, up goes down, down goes up. I tested this controller on 'Super Mario Bros. 3' and noticed the jump (A button) is very delayed. I opened the controller and flipped the rubber button press beteween the plastic D-pad piece and the circuit board--nothing changed. Does anybody know how to reconcile this issue?

p.s. please accept my apologies if I've posted this thread in the wrong area; it's my first!

Yeah, flipping around the rubber button pad won't make a difference.  This sounds like a more serious problem.  Unless you know a decent bit about electronics, I'd consider this pad a lost cause and look at getting another.