Starting today, 'media server' has shown up on this screen and drained the battery down to 60% in about 2 hours. What is this? And how do I keep it from draining the battery? Thanks
Try reformatting the card first. Obviously this would get rid of all your files, so make sure you back everything up first. If it happens again, it might be that the card is damaged.
Which Music player are you using? If the stock Music application go to the Devices tab and see if you are communicationg (sharing) with any nearby devices such as PCs, TVs, DVD players, etc.