Yes. Worked fine until now. Why do you point out that it's an optical stick?
I'm starting to wonder whether the encoder isn't just going haywire. I just checked the ohms and got a zero reading between the NO on the joysticks and GND. Then I checked for continuity again and I am no longer getting continuity--on any of them. Whereas before I was getting continuity on all of them--every single NO from every direction from every stick (plus from the direction prongs on the P360 sticks to GND).
On top of that, though, I just woke up my system to find that none of the joysticks was working, and one of the letters was repeating endlessly like the button was being held down (I have Notepad open). And while I say none of the joysticks is working, that's only partially true, cos if I moved the player 2 stick, the repeating letter would briefly stop repeating, though none of the letters associated with the the player 2 stick would be typed on Notepad. Then, even as I typed this message, my other player 1 sticks (not the eponymous P360) began partially working--left-right registers, but not up or down.
However, even as I say that I think it's the encoder, that wouldn't explain my original P360 problem, because the P360 isn't working at all, whereas my other player 1 sticks are working partially, but they're all wired into the same places on the Ipac.
Sigh . . .