Please don't flame >.< I'm just trying to contribute
A while ago I saw a thread about how you can hear voices of Arthas and his dad in the Undercity room with the throne. Well a little bit ago I noticed that if you go into SW keep, and stand around where Anduin Wrynn (the kid) is then you can hear voices if you turn up your volume loud enough.
I found it useful to turn off sound and music and turn ambiance up to maximum, because there's a lot of people there. The voice is more quiet and indistinguishable then in the Undercity, and there's whispering which sounds like a voice and makes it harder to hear what is being said, and the whispering isn't what I'm talking about, you have to turn up the volume higher.
Additionally the voice only happens occasionally, so because of all that, I don't know what is being said. >.<
I'm guessing maybe it's Anduin Wrynn's dad?