[Typo3] Multimedia - size of video window

[Jogvan Olsen]

Can anyone tell me how I can change the size of the video window, when I 
insert a .wmv file using the content element 'multimedia'.

My video is 384x288 pixel but when I play it in FE the size is only 
shomthing like 200x158.

I tried to load 'CSS styled MULTIMEDIA' and included "CSS Styled MULTIMEDIA 
(css_styled_multimedia)" in the field "Include static (from extensions)".

And this is my setup:
includeLibs.tx_cssstyledmultimedia = 
EXT:css_styled_multimedia/class.tx_cssstyledmultimedia.php
tt_content.multimedia.20 = USER
tt_content.multimedia.20.userFunc = tx_cssstyledmultimedia->cssMULTIMEDIA
tt_content.multimedia.20 {
  width = 384
  width.override.field = imagewidth
  height = 288
  height.override.field = imageheight
  stdWrap.wrap = <div class="multimedia">|</div>
  alternative.field = imagecaption
  alternative.parseFunc = < lib.parseFunc_RTE
  aparams.field = pi_flexform
}

It changed the size of my video window, but it only displays a black box 
(with control bar) instead of the video.

What am I doing wrong?

PS
I use Typo3 v3.7
Css styled content

Thank in advance
Jogvan Olsen