Prevent JW Player from playing external video in HD

Hi (my first post, thanx for this great player :))

I would like to know if it is possible to prevent the jw player plugin for wordpress playing external videos (youtube, local, etc.) in HD.

The post content is the following:

[jwplayer config="Video Afspelen" mediaid="1952"]

The video is the following (youtube):

http://www.youtube.com/watch?v=Px3ORmnGXfk

The post/video is displayed on a website that is built for 1600+ resolutions, so when I visit the website the video seems to be running in HD, don't know for sure, but it looks better than on youtube (360p). I assume the jw player plugin switches to HD because of the high resolution and because of that the video is also available in HD.

I searched in the settings of the plugin, also in the settings of the player (custom player) and here on the support pages and forum but no luck.

Is it possible to add something like this?:

[jwplayer config="Video Afspelen" mediaid="1952" HD="FALSE"]

or something like this: HD="360p" ?

Thank you!