The Media Framework is known to have compatibility issues with h.264 and .mp4 encoded media file types. Check to see if this is what your video is using. You can see in our documentation where we highlight this known issue.
Media Framework
I have created a simple tutorial to help users control their Media Asset videos using blueprints which you can find if you navigate to my tutorials on the Wiki below.
Once you have the answerhub post up, provide me with the link here in your response so I can help you there 
Cheers,