My dsi's d-pad has always been crummy - it was hard to do diagonals, and my thumb would get sore while playing Contra 4. It wasn't until after the warranty expired that I considered it might be just my dsi. I've read of people who have compared different dsi's d-pads and concluded that theirs was faulty. Well, I've been messing around with my dsi's and 3ds's innards since getting the right tools. I tried swapping the d-pad's rubber pad with the one from my 3ds. It worked surprisingly well, and I was considering getting another one for this purpose. But then, after reassembling my dsi with its original components, the d-pad was suddenly working wonderfully! It made fairly loud clicks, but it felt worlds better. As far as I can tell, I accidentally flipped the rubber pad over while reassembling it.. Perhaps this is how it's supposed to be, and my dsi was assembled with its rubber pad backwards? Just a theory. But if you can't play d-pad heavy games on your dsi, you may want to try this. Ifixit has a guide to remove the power board, which is all that's necessary to get at the d-pad. But I couldn't remove the wired connector, I only removed the ribbon cables.