embedded video – size is ignored

Hallo everyone,

I am fighting for a couple of hours with a problem that seemed to be very easy.

I just want to embed a YouTube-Video on my wordpress-site 3.5.2(theme is “responsive”). The Problem is that the Video is shown as full-screen all the time.

I tried different things:
[embed width=200]video-url[/embed]

<iframe name=”yourframe” src=”video-url” frameborder=”0″ scrolling=”auto” width=”200″

I found some tips on the Internet to Change Settings in the functions.php (http://stackoverflow.com/questions/17033662/changing-the-default-wordpress-youtube-embeded-video-dimensions) but this also did not work.

Could anyone help?

Thanks and regards,
NAV