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I have a very slow school computer and the school year is wrapping up soon. I'm using the video editing part of blender, putting in my own music and videotaping for an English project. I rendered it with the default settings (because I don't know how to change them, started yesterday) and there's no sound. I went to go see what was wrong and opened my project back up, but the ability to edit the video or audio was completely blank. I just want my complete video rendered in .MP4 so my teacher can see it;; I'd like to save it so he can hear the audio as well, but when I render it it saves as a .png and doesn't have sound.