Sounds goods. Please let me know with any updates. Thanks

Hello there,
I have exactly the same problem, Dolphin 4.0 on OSX 10.10. 1st ps2 gamepad controls both players. In the configuration screen, only input/0/USB Gamepad (which seems normal, both GP are connected on USB port 1), dolphin records the same signal for the two controllers.
Any news??
Oh I can't believe I forgot to get back to this. I don't have any issue with mine. Do you guys have other computers to check on?
No other computer, but I have tried using Dolphin on Parallels with Windows 8.1 and it recognizes both controllers fine. Although the performance isn't very good on Parallels.
Maybe the issue has been fixed with a recent update? Haven't tried any yet.
Have you guys tried the latest dev builds?
I tested the version 4.0-5569. The problem still persists...