Let's be brutal here. WMP is not a capable player. Test your video in VLC Player. If the sound works, then it's a WMP issue and not a video file issue.
My daughter started wanting to do "let's play videos." I'm using OBS to record her and Wondershare Video Editing software to edit her video. She is doing the PIP style LPs. When played as a mp4 video on windows media player you can hear her speaking and the video game at the same time like you should. Once I import it into wondershare you cant her speak but you hear the game sound. How do I ensure I can her and the game sound in the video editing software? Any help anyone can provide would be greatly appreciated.