Sticky Button on Madcatz SF IV TE stick

Hey guys, I was wondering if anyone could help with with this. My light punch button lost some responsivness; I figured it was just the button since it seemed a bit stiff at times. My solution was to swap it out with one of the end buttons seeing how I don’t use the last two gray ones. That didn’t help like I thought it would, so I’m lost on what to do next. Any help will be greatly appreciated.

perhaps the pcb on the madcatz stick is going bad.