Power drain on my digital camera?

I have a Sony DSC-H5 digital camera (5 years old, but in mint condition). It was designed more like an SLR type camera than a compact box-type camera, and is full featured, especially with a large 3 inch viewing screen on the back. The problem I've always had with this camera is the large power drain on the NIMH "AA" batteries...there are only TWO running the camera! These batteries will drain completely in approx. 10 minutes of use, or much less if you take a few flash pictures, or move the zoom lens in and out which uses extra power, etc. I have used different brands of 2500 mah "AA" batteries, but they all drain out equally fast. Would switching to a 3000 mah battery give me more useful useage time? OR...is this camera really malfunctioning internally by using up so much battery power? The camera came this way new. This model was soon replaced by a similar Sony model camera which used a DIFFERENT battery setup altogether, so obviously, the original setup was no good. Any ideas or input on how to extend battery life without costly repair will be appreciated. Thanx!