How to install Oka Mirror Audio Driver
First, download the Oka Mirror Audio Driver Here.
After downloading the package, install it. You will find an app called Oka Mirror Audio in your system that mirrors the audio to a TV. If you are a programmer, you can also find this driver's open-source code on Github.
During the installation, if you receive an error message like this:
Just go to System Preferences -> Security & Privacy -> Select Open Anyway, as shown in the following screenshot:
If you want to uninstall Oka Mirror Audio Driver, go to How to uninstall Oka Mirror Audio Driver.