I know about that, I actually jump off ledges a pretty decent distance from the actual ledge. I sprint off the ledge, with about a ledge roll's distance from it. I might still be too close at times, not sure. Which doesn't quite explain times I get knocked off the stage and then lack a second jump, which although rare, has happened in every smash game I've played, and every person I have played with. The reason why I think it's controller malfunction is because there are times when I input commands and my character will stand there and do nothing, I'm not stunned, I didn't get hit, I'm in a neutral position and try to do a tilt or smash and nothing happens, or I'll attempt to go into a quick dash and then into dash attack very quickly and my character will just stand there. Again, rare occurrence but not as rare as I would like it to be. Likewise there are times when I use UpB and it register the input until spamming it several times and already too low for it to matter even though I wasn't stunned. My personal favorite is when I hit UpB, control stick straight up and then my character does a sideB, or I flick the C-stick to the left or right and it does a NAir which happens every other time I try to do a fair or bair. This game is full of input errors, and since I don't have access to using GCube controller I can't trouble shoot it to say, oh it's the controller or the game itself. Again, this happens with both the pro controller and the gamepad. I know very well the issues you guess are talking about, and there are little things that happen in which I know my second jump was already used so I didn't have it, but there are times when I very much should have it and I don't. It's very frustrating when it costs me a game and I have no idea why it happened to begin with.