I noticed that you are not able to use the Pop Up Player using Safari. This might be an issue with the browser itself. We recommend you to remove the plug-in and reinstall it again.
This link will give you the instructions:
I hope that helps!
I went to that page and followed the instructions.
The intructions were wrong. The SlingPlayer.plugin file was not located in /Users/[username]/Library/Internet Plug-Ins/SlingPlayer.plugin. It was instead located in /Library/Internet Plug-Ins/SlingPlayer.plugin.
Nevertheless, I followed the rest of the the instructions and re-installed the plugin.
It did not solve the problem. I am still unable to use the Pop Up Player in Safari. I have not been able to use it in Firefox, either.