Logic Pro X has a new option "Off" in the ReWire Behavior menu in Logic's Preferences panel. This is the default setting in Logic Pro X. To change the setting:
- Choose Logic Pro > Preferences > Audio.
- Click the ReWire Behavior drop-down menu.
- Choose either "Playback Mode (Less CPU Load)" if you are only routing audio from a ReWire client while syncing the transports, or "Live Mode (ReWire and Internal) if you plan to trigger instrument plug-ins in the ReWire client from Logic.
- Quit and then reopen Logic Pro X.