Hi I have a Vivotab RT, model tf600t. I bought it as a spares and repairs tablet as it has a broken screen. I bought myself a charger for it, and nothing happens. When I press the power button in for 2-3 seconds an orange light flashes twice, then nothing. What does this light mean? Also the tablet does work as it did manage to power on earlier prior to this but then randomly went off :s any help is appreciated.