H264 MP4 video unplayable when exported with audio, 'fine' without audio

[swbaxter]

Premier Pro CC, 12.1.2 Build 69 (no more updates available)

Windows 8

We are editing a video recording during a GoToWebinar presentation. The source video plays fine in Windows Media Player.

Even when we make no changes to the video, if we export it from Premier Pro as an H264 MPG (Matchsource - high bitrate; High Quality 1080p HD or YouTube 1080p HD), the resulting file is unplayable. If we uncheck the "Export Audio" box in export settings, the file plays fine - but without the audio that we actually need.

We have tried switching the audio format from AAC to MPEG but the result is the same.

We have tried uploading the unplayable file to YouTube and even it rejects it.

Does anyone have an idea why this happens?

It may be a codec issue but I don't want to get the video working by using a codec other people won't have on their computers.

Steve

[premieregal]

Have you tried adding the video to the "queue" for export using Adobe Media Encoder? Or do you export only through Premiere Pro CC.  Does the file play in other players like VLC on your PC? Really strange issue!

[Ann Bens]

Post screenshot of export settings, sequence settings and screenshot of source clip in Mediainfo (treeview).