I hate the fact that he used still images, anyways the only part where I disagree with the guy in the video is when it comes to the 'Adjust Microphone Level' which is subjective to each microphone, he some what admitted that in the video.
As you here him speak you can hear the feedback because of one of two common reasons, his PS4 usb ports are set to charge the controller in rest mode or his mic level is too high.
To resolve the USB power issue on the ps4, go to Settings>Power Save Settings>Set Features Available in Rest Mode>Supply Power to USB Ports - set to off
To resolve the Adjust Microphone Level issue to to get the perfect gain you would record a quiet game with sharefactory starting from a high microphone level, save & listen the video & repeat that method moving the mic level lower with each recording until feedback is nonexistent in that video.
When in a Party Chat hold down PS button>Party Chat>Adjust Audio Mix & slide to Party Audio to hear Party Chat alot better.