I just downloaded the Movie Maker program for Windows 7 and began using it without any issues for about an hour. Randomly (or seemingly so) one of the videos I'm editing causes the internal speakers of my HP notebook to *click* and then go mute. Only the volume isn't muted and when I troubleshoot the speakers, they don't raise any red flags... yet there is no sound. No sound for any program (media player, youtube, etc.).