You may want to try using the driver provided by Microsoft* (through Windows* Updates). Some features are only available from the driver given by the system manufacturer.
You can enable/disable adaptive brightness in Control Panel, Power Options, Change advanced power settings, Display.
That was the first step I have done it to my surface pro. It only works on AC plug-in mode.
It cound not provide any help when I use battery. It still auto tune the brightness on battery!!
Please click this link then looking for #10
Another guys was also reach the problem.
It was clearly caused by the Intel graphics additions function.
Please just confront to this issue seriously.