Pad Vibration Setup issues

Hi, I have a Windows 8.1 64-bit system, and am using a generic PS2/PSX to USB blue adapter. The PCB states ZC811, manufactured in 2010, which seems like a similar variant to the other generic adapters. The pad has been working flawlessly as a regular gamepad without vibration.

I tried the universal driver listed here just now and it does seem to have worked, though vibration doesn't work as intended. The control panel is the only place where vibration is working flawlessly - both motors run consistently at max strength when requested. However emulators interact oddly with them. For example, rumble works in ePSXe, but only the big motor (as far as I can tell), and only extremely weakly, so that sometimes it's completely imperceptible. Dolphin as another example allows again just the big motor, and again fairly weakly, so that again it's sometimes impossible to feel, even in the controller config screen where you can test it. I haven't tried other emulators, but already this seems wrong. Can anyone offer me help with this issue?

Thanks

thanks for the post..

http://iaf-ifa.org/treasure-nile-slot-game-review/