MacOS X (10.13 - High Sierra) and later implements a new security feature which affects Camtasia 3 ability to install the TechSmith System Audio Capture kernel extension.
If on macOS High Sierra 10.13 or later, update to Camtasia 3.1.7. If the problems continue, try the suggestions below:
Option 1: Allow in Security & Privacy
- From the menu bar, select Camtasia > Preferences > Recording and click Install component.
- Click Install.
- Click Open Security & Privacy.
- Click Allow, and then enter the computer password.
- Try recording system audio in Camtasia.
Camtasia may prompt to install the component again. If so, follow the steps to install the component again.
Option 2: Remove Old Extension
- Open a Finder window.
- Select Go > Go to folder from the menu bar.
- Type the following and click Go:
- Move the TACC.kext file to the Trash. Empty the trash.
- Restart the computer.
- Repeat the steps in Option 1 to install the system audio component.