Simply put the Retina MacBook Pro 15" has a defectively coded speaker driver.
In Windows 7 you can see that it has 4 channels, left, right, center and sub.
Only the left and right work. The center and sub produce no sound.
The end result of this is that the tweeters (upper speakers in the photo) are the only speakers that produce sound, and the sound coming from the speakers is complete garbage. The sound quality is really bad (even with equalization), the volume is abysmal, and sounds below 1000hz are not reproduced.
This really sucks. Is there any way to possibly fix this and enable the mid-range speaker drivers in windows 7?