I am having the issue that Davelake described. I appreciate reading the suggested answer, and I can verify that starting a new session clears latency. But how do I fix this? I tried disabling all plugins, and the problem remains. I closed the session and reopened it, and Logic still spends a while "Loading Plugins..." even though they are turned off. I disabled all virtual instruments too. Something about this session is causing a latency problem, and it's apparently not a plugin or a VI. I don't want to remove the plugins. Also, using "low latency" mode gets rid of the latency for VIs, but it doesn't correct the MIDI delay issue reported above.