Has anyone else had or can anyone explain what would cause a loss of power requiring the battery to be removed and reinserted to enable the camera to be turned back on? The contacts appear to be clean. This is a special problem when doing long downloads to the computer. The computer fails to find a certain file and then, only after removing the camera from the dock and removing and reinserting the battery can the download be resumed. The removable drive icon is temporaritly lost. This has lately been happening a number of times during a single 1 gb download. Thank you in advance for any suggestions that may be offered.