I struggled as well but succeeded once I ironed out the export settings on the video.

Video Codec: H.264/AVC
Frame Size: 1280x720
Video Bitrate (critical): 3200
Framerate: 30fps

Audio: MPEG-2/4 Audio
Sample Rate: 48000Hz
Size: 16Bit
Audio Bitrate: 128kbps
Channels: Stereo