Something strange is going on with my Macbook right now. It is charged to 100% but connected to power, and the battery display on the taskbar keeps flickering between displaying 100% and a battery symbol with X in it, when I click it says 'no batteries available'. This is happening every few seconds. It started happening about half an hour ago. I unplugged the Mac and when I did the screen went black and wouldn't go back to normal. So I closed the lid and reopened it. It then returned to normal, but now the same thing as happened, and when I took out the cable the same thing happened. I don't know what's going on. Thanks in advanace.