I have been having the same problem since upgraded the sling player plugin to work with Lion. Sling are you reading these fourms? This is SUPER anoying! As a work around I have been using firefox, then using the pop out player, and then telling firefox to go full screen. This is not perfect but gets the job done. I use Safari as my main browser so I do this in firefox so the full screen mode does not effect my regular browser. Please fix this!
I totally agree. I for one have not liked their move to "browsers" from the player you previously installed (.dmg)
To fix your problem install this: http://www.macupdate.com/app/mac/23189/slingplayer
Then login and you will experience Sling how it should be "Browser free" and through a regular app. They won´t develop new versions of it and I hope people can vote for them to give us both: Browserplay when travelling / on other computers, and the old Mac app "up to date"..
Thanks for the info (and sorry for the very late reply). Although it's a great short-term fix, the software doesn't broadcast in HD, which kind of defetes the purpose of having a Slingbox HD.
It seems like the problem is in the SlingPlayer plugin itself and its inability to toggle fullscreen on an external monitor. I remember a couple years ago, flash had the same exact problem, and they eventually got to fixing it. Hopefully there's an update to the plugin soon.