MacBook Display Brightness

[deejross]

Having a strange issue that I searched for, but couldn't find anything like my experience. Recently, after about 5 minutes of use (not sitting idle), my MacBook's screen will go very dim. I hit the buttons on the keyboard to take the brightness all the way up, but it doesn't get much brighter and there's only one thing that I can do to make the screen go brighter: I go into System Preferences and click Display. The second I click that, the brightness returns without me doing anything in the Display section, so after Display comes up, I just close it out and the screen brightness is fine for a while. It seems to do this after the lid has been closed for a while and then starts dimming again after opening the lid and using it for about 5 minutes.

Any thoughts on this? Is there a way to fix the auto-dim mode without disabling it?

MacBook (white) is running Leopard 10.5.8 with all the latest updates.

 

[broad]

create a new user and see if the same issue persists with the same settings on the new user

 

[deejross]

I figured out the problem. I run Plex on my laptop and connect it to the TV and forgot to close Plex before unplugging it from the TV. That means that after five minutes, Plex dims the laptop monitor.

Thanks for the reply though.