how to completely uninstall AirBeam TV?
From https://www.airbeam.tv/faqwd/how-can-i-uninstall-the-airbeamtv-audio-driver-2/

First, find out what driver version(s) you have installed. Go to
System Preferences -&gt; Sound -&gt; select the Output tab. Look at the list
of the sound output devices.
If you see “AirBeamTV Audio”, you have
the audio driver version 2. To uninstall it, you need to delete
/Library/Audio/Plug-Ins/HAL/AirBeamTVAudio.driver
Detailed instructions:

Open Finder
Use the menu “Go” -&gt; “Go to folder…” (or press Shift + Command + G)
Copy the following path: /Library/Audio/Plug-Ins/HAL
Click “Go”
Delete “AirBeamTVAudio.driver”. You will need to enter the administrator password because this is a system location
Reboot your computer. After the reboot the driver will disappear in the system sound preferences

If you see “AirBeamTV”, you still have the audio driver version 1. To
uninstall it, you need to delete /Library/Extensions/AirBeamTV.kext
Detailed instructions:

Open Finder
Use the menu “Go” -&gt; “Go to folder…” (or press Shift + Command + G)
Copy the following path: /Library/Extensions
Click “Go”
Delete “AirBeamTV.kext”. You will need to enter the administrator password because this is a system location
Reboot your computer. After the reboot the driver will disappear in the system sound preferences