Down button also B button.
Brought to you by:
mcfly80
I've had this problem on the Linux version of Nestopia (haven't tested windows in a long time). The same thing has happened with different controllers as well as different distros of Linux. The keyboard works, but as soon as I map a player 1 controller to a joypad, the down button also registers as a b button press.
It took me a while to figure out what was happening. This is very annoying. I used a Logitech joypad and a Microsoft Sidewinder joypad.
To clarify I noticed it adds an extra line to the nstcontrols file, and I have since just deleted that one line and it works the way it's supposed to.