Fan makes a crackling, static-like noise

I’ve had my Dell Inspiron 1100 for over a year now, and it’s recently started to make crackling, static-like noises in the upper right corner of the hard drive where the fan is. This only occurs when the fan is at a reasonably high speed, and when I tend to be demanding more than usual of the CPU. There’s not an overheating issue since the laptop is in the same place on my desk as it always was, and there’s not an air blockage problem. Is there any way to fix this without taking it into the shop and replacing some parts? Could it maybe just be a small issue of needing to clean the fan?
Note: this has nothing to do with my speakers or any audio, and is definitely being caused by the fan.

 

try playing around with some compressed air. i blow out me whole laptop once every 3 months, keeps it running quiet and cool. it that dosent work, describe the sound a bit more, like something hitting something?

 

I got dell laptop (Latitude), my fan was making some similar fan noises, not all the time.
I also had a couple of keyboard keys not fuctioning all the time: K, I,and 8, so I removed keyboard cleaned keyboard connection while I was in there I cleaned everything that was visable including the fan, also I used air compressor to blow dust out (careful too much pressure can cause dammage).

Now my Fan is quiet and all the key's Work!

 

Problem Fixed

Well, I took apart my laptop and about 20 tiny screws later, I was able to lift up the keyboard. Turns out that there were a few pieces of hair stuck in my fan blades. I gently pulled them out, cleaned the dust off of the fan blades with a q-tip, then put everything back together. The noise is gone and everything seems to be running smoothly. Thanks for your help!