I have a Super Dual Box at home, and it works great with the Start+Select+Up fix. Now I just got a new one for a friend of mine, and it came in slightly different packaging (it claims on the back to be compatible with DDR games, mine doesn't say that), and came with a different floppy with different drivers.
It seems that they tried to fix the axis problem themselves by, instead of treating the arrows as buttons, detecting when both up+down or left+right are pressed, and alternating rapidly between the two. This is really a crappy way to solve the problem, since it still doesn't hit them *at the same time*, so you still end up missing those jumps unless both "presses" stay within the window.
Has anyone else seen this with the newer models? I'm thinking this is probably a problem in the driver, so I'm going to try tonight to use the drivers that came with my SDB and see if that'll just let me use the 3-button axes-off fix, and I'll report back my findings.
EDIT: After looking around a bit, it looks like this problem is also referred to as a "flicker" or "strobe" problem.
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