Working on a project recently where we were using an embedded youtube video iframe, as well as the Yahoo! Web Player.  Autoplay was enabled on the youtube video.

If the Web Player was minimized, then the first time the user would click on a media link on the screen — the youtube video would restart!!!

If the Yahoo! Web Player was displayed to start with, then this did not happen.

As it turns out, this is controlled by the wmodeoverride option to the Yahoo! Web Player.  If it is set to false, then the youtube-reload-issue does not happen.

http://webplayer.yahoo.com/docs/how-to-set-up/#customize

parameter: wmodeoverride

To prevent itself from appearing behind embedded YouTube videos, the Yahoo! WebPlayer changes the wmode setting of these embedded videos. The wmodeoverride parameter allows you to turn this feature on or off. Set wmodeoverride to ‘true’ to turn this feature on and set the parameter to ‘false’ to turn it off. The default setting is ‘true’.

<script type="text/javascript">
    var YWPParams = 
    {
        wmodeoverride: false
    };
</script>