Late 2012 iMac Internal Microphone - Poor Sound Quality...?

Hi there

Does anybody else find that the sound quality of the 2012 iMac is very subpar? I've had a number of complaints from people I've Skyped with that the sound quality is awful. I recorded a test sample using Quicktime, and it really doesn't sound good at all.

Here's a link to the sample:

https://dl.dropboxusercontent.com/u/7035139/Test.m4a

Wasn't this one of the selling points of the machine? Some kinda funky multi-mic setup to record clean sound? In real life, I don't actually sound like a robot, and there isn't any echo in my room 😉 Have I got a defective machine?