I have not heard of this problem, but
it sounds like something that Canon tech support has probably heard of before.
Here is a link:
You can get support by email or by telephone.
I got this camera less than a month ago and I am having some problems with it. Sometimes when I try to take a picture with it, the pictures turn out black. I push the button, it beeps, waits for about 3 seconds and then takes a picture that is just black (I'm using the viewfinder when this happens). Also, when I am in picture mode, it will sometimes not switch between the LCD and the viewfinder. I can hear it change, but the LCD just comes up black. Whenever I am at home and trying to find what is wrong, it works fine so is this something I am doing or should I take the camera back?