This is another AC power/battery problem, but it seems subtly different from the others I can see in the forum.
Firstly, it doesn't seem to be charging, it won't run from AC, but it *does* seem to be taking power from the adapter. I say this because when I plug the AC in, the white LED lights up, and the orange one starts flashing. It won't boot though, whether or not the battery is in. I've tried another charger and it makes no difference.
When this first started, the orange light started flashing even though the battery had plenty of power. I plugged the AC in and it didn't seem to be charging the battery. Once the battery had completely run down it still ran from AC, but unplugging the AC caused it to shut down immediately and refuse to boot.