I am splicing several clips together with audio. Everything plays fine in preview. I have set the start and end frames, changed the format to ffmpeg, container mp5, codec h264, audio codec aac, everything else default. When I click render animation the screen pops up grey and there is no progress bar at the bottom of the main screen. Under tools, I checked all the slots and it says image won't load. So far I have tried changing the viewpoint to zero and tried without the audio. Nothing is saving to the output location.