Why Does Smyle Mouse sometimes thinks I am smiling when I am not?

Try one or more of the following: 
1.  Perform a calibration and make sure to smile when prompted during the process. 
2.  Make sure you are facing the camera when working on your computer so that your lips, nose, and irises of both eyes are visible to the camera without obstruction. 
3.  Make sure facial features are being detected correctly and smoothly by checking the camera view displayed on the main Smyle Mouse window. 
     Correct the lighting situation such as low light or intense backlight, if required. 
     Try using a webcam that performs well in low light.