Optio 450 - Powers Down

Hi, Optio 450 has developed a fault - I think... currently it is powered off but the lens protector is not closed.

On powering it up, I see the LED display light up, but the camera powers down immediately, again without the lens protector closing.

On attempting to understand the prob, I discovered that if I change the mode of the camera to Sound only, the camera will power up and stay on. However as soon as I change the mode to "taking pictures", it immediately powers down, again with the lens protector not closing.

The camera is only 8 months old.

This is causing much wailing and gnashing of teeth, particuarly with a new baby and Christmas upon us. Any thoughts :

I guess I should also have mentioned that the battery is new and fully powered up...