Bring the Mystery Mask to Wildlord Antelarion in Ruuan Weald.
Ok, it should work now. What is it, you ask? Why, it's a communication device - it allows those blockheads to communicate with each other. You know, the Burning Legion! I would suggest that you hand this mask to Wildlord Antelarion. He's over there pacing around. Always moving, he is.
Well get moving, he's been trying to get his hands on one of these for sometime now.