Using Extensions Manager, check to see what version each FreeMIDI extension is. FreeMIDI PowerPlug and FreeMIDI System Extension should be version 1.46, FreeMIDI Softsynth should be version 1.31.
If they are older versions, you will need to reinstall freemidi.

1. Drag the following items into the trash"
- FreeMIDI Applications (in Macintosh HD)
- FreeMIDI Folder (Macintosh HD >> System Folder)
- "FreeMIDI..." Extensions (Macintosh HD >> System Folder >> Extensions)
- "FreeMIDI..." Preferences (Macintosh HD >> System Folder >> Preferences)
2. Restart your computer.
3. Load the Digital Perfomer 3 CD, and click "Install Digital Performer"
4. At the install screen, change "Easy Install" to "Custom Install"
5. Click the triangle next to Digital Performer to disclose the list of items. Place an "X" in the box next to "FreeMIDI"
6. Click the install button to proceed.
7. Restart the computer as requested.
8. Launch FreeMIDI Setup, follow the quick setup tips to create a new configuration.
9. Leave FreeMIDI open while launching DP.