Steps to reproduce:
1. Open attached project
2. Open "Main" scene
3. Put a videofile in the PlayVideo Script's Clip Field (link attached)
4. Assign the videofile to "VideoQuad" PlayVideo component
5. Select VideoPlayer renderer to "VideoQuad" game object

Expected result: The video should start playing after a 5 second delay

Note: Only certain types of videos can not be played, it does not seem to depend on the format of the video.

Reproduced on: 2017.1.0a6, 5.6.0f3, 5.6.0b11, 5.6.0b4
Not reproduced on: 5.6.0b3,

Regression since: 5.6.0b4