Hi everyone! I have a Macbook Pro 13" Mid 2009. It has always been good to me and dead silent until recently it started to develop a loud continuous buzzing/humming sound. It is so loud that it is pretty difficult to hear anything thats playing. I'm fairly sure its the fan making the noise. What's strange is that it's at a fairly low temperature of 55 degrees C and the fan speed is at approximately 2000rpm. The noise is not only annoying but worrying Does anyone have a positive idea on what the problem is? Is it simply excess dust? If so, how do I clean it? Thanks in advance!