I have a problem where the transform job throws an error. Transform job Error

The way the file is uploaded is done using a website i have set up. The websites takes the files and splits it into filechuncks. Then the chuncks are stored on the server and combined in the correct order. The combined file is then uploaded using the api provides by microsoft for Azure mediastream services.

All the files are mp4 videos and a lot of them can be uploaded, but some of them fails. When i try and play the combined file it works, and all the meta data is there. Meta data for video file that is failing

What i think is going wrong:

1. The combining of the files somehow corrupts the file even though its still playable.
2. There is some error in Azure that i cant change.
3. The encoding of the video is wrong somehow.

All help is appreciated :D