This is not likely the cause, but just to get it out of the way.....
The camera is set to take a burst of three pictures, probably one second apart. This is a software setting that presumably can be changed to one or two pictures I would think.
After this burst setting, do you have the option to set the time the camera waits before it can potentially shoot another burst?
Let's assume you have all that set to your liking, I'm curious to know what happens if you change those setting? For example, keep the 3-picture burst but change the wait time. Does that change anything?
If it doesn't it, S.T. could be right about needing a firmware update. But, before that I would try to reboot the camera. How to do that, if it's even possible with your problem camera, is always something of a mystery. Google the camera name and "reboot" or "hard start." If that fails, I'm thinking there's a bad chip in the internal circuitry. And back to the factory it goes!
