Fix Core MIDI problems with OSX
Caution: Rewire users have been reporting that after entering the Terminal command below, Rewire stops working. I don’t use Rewire, and have no experience with it, but I’d bet that reinstalling Rewire afterwards would fix the problem. It probably installs some kind of virtual driver to your Midi drivers which the Terminal command would delete. The two options are therefore to reinstall Rewire after cleaning your Midi drivers below, or to copy and save whatever component that Rewire installs before using the Terminal command, then drag it back into the folder indicated below when you are done. I need some feedback from a Rewire user, though, before I can be sure. Please comment of email me if you have experience with this.
– Now on to the post –
Is your MIDI dead? You might have just used Migration Assistant to move from one computer to another. Or perhaps you upgraded to Leopard. Symptoms include:
Can’t launch programs that use midi
Can’t open Audio Midi setup utility or the Midi portion won’t launch or jams
Getting messages telling you to update or reinstall your drivers
Getting messages telling you that Midi Server won’t launch
Core Midi doesn’t run
Opening Terminal.app and entering this command should remedy the problem:
sudo rm -rf /Library/Audio/MIDI\ Drivers/*
You’ll have to enter your administrator password. This problem had vexed me for a few months, effectively disabling Core Midi – first after having run migration assistant, and again after upgrading to Leopard. I finally fixed it yesterday and can now run midi again. I hope this info will help others who are searching for a solution. I have added some distinct keywords to this message to make searching easier.
Note: If the above does not work, you need to make sure the directory below is empty, before you reinstall your interfaces. The location must be correct with no alternate spellings. It should also be ok to remove the drivers manually (by sending them to the trash), but the Terminal command helps in that regard. Note: you will likely need to reinstall any real Midi drivers that you need, including Rewire.
