I just bought an E-PM2 and using the 14-40mm kit lens. I took some pictures in the house and noticed sometimes it would appear to take a long time to focus and sound like grinding. But other times its really fast. The end result of the picture is its blurry. I'm not sure, but I think its only when I'm taking pictures of people. Its on the default Auto setting. This is with or without a tripod. Is this a combination of low light and lens limitation? Should I send it back?