Question: WordPress or my theme fails to embed this video URL:

`https://www.youtube.com/embed/vsTrAfJFLXI?rel=0?controls=0` 

but works with this URL:

```
https://www.youtube.com/watch?v=vsTrAfJFLXI

```

I need to get rid of the youtube control buttons in the preview, but cannot use embed or the iframe because that just creates an hyperlink. Any ideas? 

WP version 3.7.1

Answer: 
Having `&controls=0` instead of `?controls=0`solved the issue for me.
Have you tried switching off all your plugins and changing the theme to see if anything might be causing a conflict of some sort? If it works, then start by changing your theme back, refreshing the page and seeing that works. Introduce the plugins one by one and refresh the page to see if any of those might be the culprit?