It seems to me that the video is set to display at a weird resolution. The video data itself is fine, it's 1280x720, but in the Matroska container it's set to display at 1551x720, which causes the video player to stretch the video to that proportion. This can be easily fixed by re-muxing the file, while setting the video aspect to 16:9.
Comments - 3
olivo28
oaso
Webbmaster62 (uploader)