After i resume windows from hibernate, brightness control is not happening using quick keys. Every time i need to go to control panel & change manually. Other quick key functions are working except the brightness control. The brightness bar stuck like below.
Even killed quickset process & opened again, nothing useful in it. But when i reboot the system it starts working, and problem starts again when i hibernate.
RE: brightness control not working after hibernate
I take it that when you notice this, restarting the notebook corrects the problem every time? I am not suggesting this as a solution(sometimes i would rather see the dentist than have to restart one of my PCs) but I want to make sure that this isn't a hardware issue.
When you notice the problem with the brightness keys try holding down FN when pressing them and see if there is a change.
As another test go into Windows and change the power plan and change it to "high performance" before hibernating the notebook. Before resuming plug in the AC adapter and see if you are now able to adjust the brightness, if you are able to then this becomes less of a problem with the function key behavior and an issue with power management.