When Auto-Brightness is enabled, and I turn the screen on from sleep, I sometimes get anywhere from 1 - 5 seconds of lag while the screen adjusts brightness. While this is occurring, I cannot use the phone. Once brightness adjusts, the lag disappears.
I tried to reproduce the issue you're having.. With Auto-Brightness enabled I don't receive lag waking up from sleep..
Thank you for testing this. I don't get lag every time, only when auto-brightness has to adjust. Allow auto-brightness to turn itself up while you use the phone under a lamp. Then, turn the screen off and go into a dark room. When you turn the screen back on, you should see the lag while the brightness adjusts to dim itself. Or vice-versa I have had this problem with every version of CM I have used for the Thunderbolt. I've also read of others having this problem in the threads on rootzwiki and xda. I've also noticed that not all people seem to have this problem either. Could it be something that is phone-specific?
I can confirm that this is definitely the case for me, thought it seems to be a bit better in the latest 1.6.1 release, I still get an some lag when waking the phone and the auto brightness starts to adjust. So much that I can't enter my pin in enough time before the lag catches up.
To fix the issue I have just been manually changing the brightness with the status bar widget.
On my original device I did not have this issue and then I had to get a replacement device. This issue showed up and drove me crazy! Switching off auto-brightness did not help at all. I had to get ANOTHER replacement device for other reasons and guess what, the problem is gone! It seems that some devices have the problem and others do not.
I can confirm this is doing the same thing on my device.
I can confirm that this happens with my device as well. Sometimes the lag is so bad I can't unlock my phone before the screen goes black. This especially happens when the auto-brightness needs to go from each extreme.