iBuffalo Gamepad Problems

[Youn]

I don't suppose anyone here knows how to fix this, or can point me to some resources to help me?

I bought this gamepad to replace my failing 8bitdo controller (its direction pad rubber wore/broke down, causing massive frustration moving characters around a screen)

The problem with the iBuffalo controller is, when I push right and any other button, that button becomes temporarily turbo-ized. I've ripped it apart and even removed the turbo button, thinking maybe it was getting pressed by the pressure of the d-pad, but it must be something else. I did notice the circuit board was rather dingy with white powdery stuff smeared around the surface and what appears to be scratches... *sigh*

Is there anyway to completely disable turbo by modifying the circuit board, or is this just a junk controller with bad QA. There is no returns on it, but with such great reviews I figured luck would be on my side...

https://www.amazon.com/Buffalo-iBuf...=2025&creative=165953&creativeASIN=B06XWD8QQJ