for some reason, my vegas pro 13 is just rendering black screens when ever I render in the .mp4 format. There are videos in the timeline with audio and everything but when it renders I can see it rendering the video fully but when it completes I view the video and it has only rendered the audio and shows a black screen, I switched to media player and it is still a black screen even on there. This is extremley fustrating and it is happening on all of my projects. Does anyone know how to fix?