Video Material/Texture stretching problem

I created TV screen in my project and made it so that it plays a video with sound, i tried this with the SAMPLE video of UE4 and there’s no problem there.

However when i try to add in my own video it gets stretched:
http://puu.sh/sqBAb/d8814d392a.png

The video is an MP4 file just like the sample video. Any idea how this came to be?