I'm having a weird problem with my controls. For some reason, the game thinks I'm holding down "right" when I'm not touching a thing.

I've tested all my hardware to see if it was the problem. Obviously, not the case. I've tried both the original config, and the newer one. I also have both patches installed. Below is a verbatim copy of my input file (original config) if it helps.
Keyboard
1. "Select" 32
2. "Exit" 45
3. "Misc" 30
4. "Menu" 17
5. "Toggle" 16
6. "Trigger" 18
7. "RotLt" 44
8. "RotRt" 46
9. "Start" 31
10. "Select" 33
11. "Up" 200
12. "Down" 208
13. "Left" 203
14. "Right" 205
Joystick
1. "Select" 225
2. "Exit" 226
3. "Misc" 227
4. "Menu" 224
5. "Toggle" 228
6. "Trigger" 230
7. "RotLt" 229
8. "RotRt" 231
9. "Start" 232
10. "Select" 233
11. "Up" 252
12. "Down" 253
13. "Left" 254
14. "Right" 255