I over-edited a piece of a video and am now missing one word in instructiosn: enter. I want to add that word to the existing audio and, I suppose, extend the video for a moment. I looked for a way to add to the audio only but did not find it. Is there an easier way to do this than splitting the timeline and putting the tiny recording I made of saying "enter"? I fear continuity problems, i.e., the screen recording for the tiny segment might not match exactly the screen appearance before or after it. Any suggestions? It appears that I cannot split until I separate audio and video. Is that correct? Why? I am using Camtasia 9 on Windows 10. Thanks.