I could be wrong, but I think I know the answer.
You are not getting enough power into your joystick through the usb port you are using. If you are using the front USB ports on your PC, try changing to the back USB ports. On some older computer the front ports are USB1 and the back are USB2 I have been told.
If that does not work, you need to get yourself an external powered USB hub. This should solve your problem.
If that does not work, you need a new joystick, or to fix your current one.
Good luck!