Okay. I have tried to replicate. I cannot. I have even found another joystick to see if it is something to do with complicated setups. It still works for me, so:
Download and install the debug wxLauncher from here
into the wxLauncher folder that is in the Diaspora folder (don't forget to exit wxLauncher before installing).
Change your settings to what you need to do to make it fail.
Run wxLauncher and the debug FSO and post both logs (attach them because they will probably be too long to post in the thread).