I have bought 5 different Lumix point and shoot cameras from Panasonic. Each worked great until I noticed dirt, usually small hairs or spots appearing on my photos. Despite all precautions, after about half year of use, dirt has ruined each camera. I don't have the skills to open the camera to remove the small hairs/dust and repairs would cost as much as a new camera. Does this problem appear in other brands or just in Panasonic? I have used both Canon & Casio cameras in the past, also small point and shoot, and never had this problem. Should I use a different brand?