Macbook Pro Retina 15 has a creaking noise even without touching it

Question

These days I found that my macbook pro retina Early 2013 Model has a creaking noise when the CPU and GPU's temperature is going up to 50 degree Celsius, which should be normal temperature when you only run the machine for web browsing and video watching.
And I got this creaking noise sudden without my hand put on anywhere close to the machine, it came out itself. And I have checked that:
1. it is not the sound from the spring on the main board.
2. it is not from the buttom because I tried to removed the buttom and use the machine the noise still there
3. it is from all over the keyboard, most close to the screen.
I am doubting that it is because metal moving while heated.
And I made a video to record it then show it to "Genius" in apple store. But they claimed that they couldn't hear anything, since me and my friend have all comfirmed that it is exsisted!
Watch the video at max volum and at around 3 SECOND and 35 SECOND, there comes the noise.
https://www.dropbox.com/s/o7kqww05d1e2avv/03__35.MOV
See if any one got the same issue.
Thank you and wish you don't suffer from this.

Answer 1

Believe it or not, Flash REALLY isn't the issue.
It's hardware makers making devices with less processor performance and requiring software makers to fit into a certain requirements of such. Namely iPhone, iPods and iPads.
Flash is designed to give a lot of features and work across many operating systems, browsers and platforms as a write once solution.
Flash has a certain level of processor performance requirement, which hardware makers like Apple want to build less powerful machines using less expensive processors.
Apple has removed Coverflow 3D effects from iTunes and discontinued the 17" MacBook Pro, leaving only the 15" as having a more powerful 3D capable graphics capability.
So Apple is obviously on a anti-heat/performance quest as they further thin up their hardware, trying to kill Flash by punishing Mac users who want to run it.
Flash runs without a fan sound on my older Mac with dedicated GPU and older OS X verison, no sweat.
Head to your System Preferences > Energy Saver and if you have it, uncheck Automatic Graphics switching, this will use the dedicated GPU and shorted battery life, but if your on power should reduce the heat and fan noise.
Another option is to use SMC fan control and set the fan default speed slightly faster, this will keep the machine slightly cooler and not trigger the higher fan speed as often.
If your running 10.8, you will need to System Preferences > Security > downloads to "Anywhere"
SMC FanControl is over at MacUpdate.com.