I had some problems seeing which plug was in and which one is out. It is'nt labeled on the card. I was looking for the manual but could'nt find it. And i believe that the card is "upside down" as well
But i saw that if you remove the protection plugs there is a LED lighting in the OUT plugs.
No surprise there but it saved me some time and frustration.
BTW. there is no danger in plugging/unplugging optical cables when the card is on as it is only light running in the cables.