Streaming from SharePoint chops up MP4

I've uploaded a ClipChamp MP4 to SharePoint.

This upload contains the complete information I want to display. I verified the upload:

1. uploading through SharePoint's web-interface to a document library
2. monitoring this document library as a synced OneDrive map.
3. checking the uploaded MP4 by redownloading through OneDrive. Success! It contains all information.
4. checking the redownloaded MP4 in MediaPlayer. Success! MediaPlayer shows all information and the correct duration of the MP4.

But streaming from SharePoint clips the contents of the MP4 at about 5/6 part.

Therefore sharing the MP4 by URL does not provide the audience with the correct information.

The length of the MP4 as estimated by SharePoint streaming is even shorter than 5/6 of the total footage.

Now I don't mind voices a bit pitched.

But I do mind SharePoint streaming is not showing the final 1/6 of the footage, at all.

How do I stream the complete footage from SharePoint?