Hori HRAP EX button is not responding well

Hi , i searched for a solution to this, but all i’ve found are threads dealing with the T.E roundhouse buttons having problems. Anyway, I’ve had my hrap for about a year and a half putting in some very long hours with it. I tried training mode with ken getting in some practice from block strings into kara throw noticing that only 20 percent of the time the kara would come out and the other 80 a f+mk would come out. I turned on input display and noticed that my lk button would only respond maybe 5 times out of 10 presses. Every other button works fine but this is really affecting my throw and tech game. Anyone ever have this problem? Would it be the wiring? The PCB going bad? or maybe the button itself? I was thinking about just swapping my 3ppp macro button with the lk button to see if that works, but I’d like to know if it might be something simpler that I’m missing. Thanks for any help.

IIRC, the HRAP EX uses the ‘Hori’ pushbuttons. If that’s the case, then it’s probably time for you to do a button swap. Swap it out with some good snap in buttons and you should be set.
If you want to test to be certain what is causing the problem, move the pair of wires going to the Short button with the pair of wires going to Jab. Go into training mode, mash on the buttons. If the Jab button only sometimes activates the light kick, and the Short button always activates the light puch, then its a wiring/pcb problem (but its damn unlikely). If the Jab button always activates the light kick, and the Short button only sometimes activates the light puch, then its definitely the pushbutton, and you should replace it. If you haven’t replaced them all with good Seimitsu or Sanwa buttons, then go ahead and replace them all so you dont have an oddball button.

Thanks for the info man. I forgot to mention i bought it on eBay with all button and joystick mods done pre-purchase. All sanwa products. I’ll try this out as soon as I can round up some tools. Anyone know what size nut driver the ex needs?