Originally Posted by EVOlution3
I notice a lot of you are looking at it as a software issue. I work as a Sprint technician and have noticed this on several customers phones. It appears that the battery is a little loose. If you remove the back cover try and see if your battery can shift from side to side. I've noticed on the customers that have this complaint the battery seems looser than other 3D's that are working fine, like mine for example. I would exchange it, and for the time being you could try wedging a small piece of paper or business card cutting in there to hold it in place better.
Just checked my battery, and it's not loose at all.