If you use pro audio applications with OS X and are finding they hang when launched, this could be because of faults with third-party drivers for your MIDI instruments.
Music software company Avid has a music-editing package called Pro Tools that you may have installed on your system if you work extensively with audio. This package supports MIDI devices, but early versions of the program may result in a driver conflict with Apple's CoreMIDI framework for handling these devices. As a result, if you have Pro Tools installed and try to launch other audio-editing applications then you may see them hang when they try to initialize the MIDI system, and may sometimes see a folder called "CoreMIDI.framework" bouncing in the Dock.
This issue apparently results from an incompatibility with ProTools 8.0.3 or earlier, which was a version that supported PowerPC systems. If you have used this version on your older Macs and then upgraded to a new system, you may run into these hangs if you install other MIDI-handling software.
Avid has since released a number of updates for Pro Tools, so if you see these hangs then check your version of Pro Tools and upgrade to at least version 8.0.4. However, if you do not wish to upgrade or cannot for some reason, you can clear this problem by performing the following steps:
- Open a new Finder window
- Go to the Macintosh HD/Library/Audio/MIDI Drivers/ folder
- Remove the file called "DigiDioMidiDriver.plugin" by moving it to the desktop or any other location, or by simply deleting it.
After this procedure is done, Logic and other audio programs that use MIDI should launch normally and not show the bouncing CoreMIDI.framework folder in the Dock.