I made this short video to test the audio and video quality of the Blue Yeti microphone and the Logitech C920 webcam using Screencast-o-matic. Sometimes if you use the audio from another mic like the Blue Yeti, but record your video another source, such as I do with the Logitech C920 Webcam, there can be some voice-to-video lag. When the lag is present, the lips of the speaker will be out of sync with the audio and it can look like a badly dubbed 1970’s Kung-Fu Theater film.
In the video below, I tested using just audio from the webcam, and then audio from the Blue Yeti mic, to see if there was any lag. I had just restarted my computer, so the internal memory and page file was pretty empty, and I had all other apps closed except for Screencast-o-matic. I did not detect any lag in the video from either audio source. The sound quality is also noticeably better using the audio from the Blue Yeti microphone. It appears that if you find lag, restarting your computer and closing all extra applications will help with producing better quality, and in-sync, audio and video.