There are lots of reasons why this could happen. At a minimum, it could be isolated to your ISP. To determine the actual cause, you should look into using AWS logging. AWS provides a logging mechanism so you can see what's happening when your video is requested from a user. You can also look into using AWS caching by enabling CloudFront.
Windows desktop software for creating and managing MRSS, JSON, and FireTV feeds @ https://github.com/rrirower. No Programming, JSON or MRSS knowledge required.