I am experiencing sluggish graphics performance in logic 9 after upgrading to OS 10.8.5. I upgraded so that I could install Komplete 9. When working in Logic I get real sluggish glitchy graphic performance especially using the channel EQ. There are other third party plugins that have issues as well. I have looked into the discussion forums within Apple support. This is a very common issue. It seems to be a problem with ML. There are users experiencing this issue that have newer systems than mine. It gets so bad that Logics GUI becomes so unresponsive that I have to wait for the system to catch up. Early 2009 Mac Pro 8 Core 2.26, 6 Gb RAM Any help would be greatly appreciated. Rob

Hi Rob, Hope you're well (aside from the obvious issue with L9!) I've pretty much switched over completely to Logic X... and am teetering on going from 10.8.4 straight to Mavericks... I'm wondering if this issue is related to the latest Mountain Lion update... as I found Logic Pro 9 fairly responsive on my MBP in earlier versions of Mountain Lion. Sorry I can't be of any more help...

I think it has something to do with the ProKit framework. I installed OS 10 Mountain Lion which automatically updates the ProKit framework from 7.0 (In Snow Loepard) to ProKit 7.3. I used my Snow Loepard Vlone drive to acces my System folder on my Mountain Lion drive. I moved the ProKit 7.3 folder to the trash and then dragged the 7.0 ProKit in its place. I rebooted under Mountain Lion and Logic crashed at launch. So I had to replace the ProKit 7.3 folder. I can't install the ProKit 7.0 file from Apple downloads because the installer detects a newer version and prevents it. I do believe this is the problem based on what I have read on message boards. I feel I'm close to solving this issue but I don't want to take any more chances with my system folder without knowing exactly how to do it. Thanks for your reply. Rob