Not really the same issue but good to know it's a known issue.
Macbook Pro Retina 15" Mid 2012.
2.6 Ghz iCore7
Graphics NVIDIA GeForce GT 650M 1024 MB
Premiere Pro CS6 (6.0.2)
Source clips: H264 and DV tape
I added additional software/ hardware information.
Found a fix for now. Need to change the Playback settings to Mercury software only instead of the default Open CL.
I am not sure I should install a driver in a MPB? everything is controled via the Software Update app.
>not sure I should install a driver
I am on Win7 so may only say that I save a "few" Mac discussion links for questions like yours... but I really don't know if you "should" do something, or not
Over on my side of the aisle, it is VERY common for a Windows update to change "something" inside Windows that then requires a driver update
If whatever is in the link I posted does not convince you to do something, at least you have a fix that works for you
I won't risk it for now. For my type of work there are other editing solutions.