Some of you may already know about this but I figured I'd post a quick overview of how to improve the feel and responsiveness with a small piece of thin card. I bought an old busted up original Gameboy Advance. It was beat up pretty bad so I swapped it into one of those third party shells. During the swap I noticed the original d-pad membrane was torn so I had to use the third party one that came with the case. It felt pretty mushy and required a lot of force to get the up direction to register. To improve things all we need to do is give the d-pad a little more height. Open up your GBA until you get to this point: At this stage it's also a good time to give the contacts a clean with alcohol if they appear to be dirty. Remove the d-pad, roughly cut out a piece of thin card into a circle (cereal box card works well). Punch a hole in the centre and sit it on the central spoke of the d-pad. Trim up the card and increase the size of the hole in the centre so the d-pad membrane can fit properly into the d-pad. Reassemble the GBA and see how it feels. You may need to experiment a bit with thinner or thicker card but you should notice an improvement right away. This really made it feel quite a bit more responsive in my case and it completely fixed the upwards directional input. As a side note you can use the same method on Xbox 360 controllers to drastically improve their d-pads as well.