I have been having this issue for a while, so I thought I might as well see if I can find a fix.
When I've recorded my gameplay and go to edit it for uploading, the editing program (I usually use Vegas Pro 12) crashes at certain points while rendering or playing back the video file. Sometimes at the point where the program crashes I can see a sharp audio spike at the same point in the game and mic audio, but the video seems unaffected by this. Other times, there's nothing in the audio track that is out of place, but the program continues crashing at the same point. My only way around this has been cutting out the "corrupt" areas, which is a second or two of footage, and then pulling the tracks together again. This however means that the video could be skipping a couple seconds of dialogue or commentary (not ideal). I have tested it in multiple video editing programs (Pinnacle, Magix, Windows Movie Maker) and they crash at the same spot so I know it is the video file. Another issue I've been having (and maybe it is related somehow) is that the game audio gets further behind the video as playback progresses. So by the end of the video the game audio is 2-4 seconds behind. My commentary however is unaffected and stays in sync.
Any and all help is appreciated! Thanks!