WANTED: Murmur's Whisper

WANTED: Murmur's Whisper is one of the random heroic mode daily quests given by Wind Trader Zhareem in Shattrath City.

Objectives
Wind Trader Zhareem has asked you to obtain Murmur's Whisper. Deliver it to him in Shattrath's Lower City to collect the reward.

This quest may only be completed on Heroic difficulty.
 * Murmur's Whisper

Description
When I'm done speaking, you may not want to take this commission.

I have an eccentric client who specializes in the study of dead realities. It is rumored that the being known as Murmur destroyed the last world from which he was summoned. The professor is interested in examining his 'whisper' as he called it to understand how it is that Murmur accomplished such a feat.

Will you journey to the Shadow Labyrinth within Auchindoun and retrieve it for me?

Reward
You will receive:

Progress
I'm not even certain what form a whisper is supposed to take in the physical world, but the professor assures me that you'll know it when you see it.

Perhaps it is something akin to the being's voice box?

Completion
I was worried that you might not return. I trust that you didn't go deaf from fighting Murmur?

Here is your reward. The professor will be pleased no doubt, though I worry what he ultimately wishes to do with this thing.

Come back tomorrow and I will have another request for you to fulfill.

Gains
Upon completion of this quest you will gain:
 * 16,250 XP
 * +350 reputation with Lower City
 * +350 reputation with the Consortium

Details
This quest simply requires completing Heroic Shadow Labyrinth. It was added in 2.3 as part of a series to give more incentive to run Heroic instances.