I had the same problem with the d-pad thingy, I looked up controller issues on this forum and found a similar issue with an other controller. This issue was fixed with a custom kernel, I tried this method and it worked flawlessly, even 4 player bomberman on pce works great. If you search on my name on this forum you should find this topic. I don’t have much posts so it shouldn’t be that hard to find ;)
Reply To: Has anyone used the Raphnet 4x SNES/NES USB adapter circuit?