YouTube iframe embed not starting in HD

Question

I\'m trying to embed an HD YouTube video but no matter what I try, it only ever seems to load the 480p version.

According to YouTube, embedding an HD video is as sim

Answer 1

I might be a little late, but I just discovered it only looks at the height of the video player.

When I try to embed a video 1000px wide, but only 408 pixels high (2.35:1 matte) it selects 360p >:|