I am trying to edit raw footage from 3 cameras. I have them all trimmed so they are starting and end within frames of each other. I have synchronized them using the audio sync tool thingy. I have the whole thing set to the multi-camera editing settings but my preview window only shows the video on the top layer. Everything I am reading suggests that the program should automatically preview each of the video tracks simultaneously but it just isn't happening and I can't find whatever setting it is that will make the preview screen shift to showing all three tracks. What am I missing? Any help will be greatly appreciated.