Comment 2 for bug 1238695

I'm having exactly this problem and the display is highly unstable from the moment the device boots. Sometimes the display is bright, but it always flickers back to very dim (the graphics are barely visible). Touch is also very slow to respond, sometimes not responding to gestures at all.

OTOH, rebooting without mir doesn't seem all that much better. The screen will still go blank randomly, with limited response to touch or button pushes. Then the display comes back and is responsive for a bit before going blank again rather quickly.

Maybe I've got busted hardware? I've flashed it several times without improvement. I'm going to try to factory reset it to see if it's a hardware problem.