How do I set the CMSS setting in PlayCenter 2?
You will need PlayCenter 2 to be in the small player view mode. You can change the view of PlayCenter 2 using the buttons in the upper right corner of the player. Once you have it in player view, click the arrow pointing to the right in the middle of the player to expand it so that the number pad is showing. You will see cmss at the bottom of the window now. Click on this and you will have two options: off and movie mode. Select movie mode in order to get surround sound from all audio sources.