I took a quick look at the Presentation in your Company, and it looks like it is playing a live stream, not a video. Am I looking at the correct Presentation? Depending on the signal, network reliability, and video quality of the signal, this could affect the playback on a device.
I see that you have 2 MP4 videos in your Storage folder, and I wonder if you would have better playback quality using WebM instead of MP4. Check out this knowledgebase article for more info on supported video types and converting.
If you are still having issues after converting, it may be worthwhile to contact email@example.com to see if they can investigate to determine if your device is having a hardware issue.