Why do clothes produce sounds after being in front of a computer for a long time? Quite often, after sitting in front of the computer not moving a whole lot for a long time my upper body clothes (usually sweaters) make soft crackling sounds when moving or specially when taking them off. It affects more a certain type of thick materials (wool I think) than thin clothes.
Why does that happen, does it has to do with electricity, radiation, temperature, waves, a mix or something else?
It does tactually feel a little like static electricity from rubbing a balloon in 
clothes, and the computer does emit some warmth temperature.
Does it has to do more with the computer's monitor, or maybe some type of radiation? As I notice it more with an older laptop at work than my modern desktop at home.
Without making the question too opinion based, is it something slightly concerning/unhealthy that should be reduced in some way (maybe a screen filter/pellicle) other than the obvious solution of being less time in front of the computer with more regular breaks and maybe moving more?
 A: Some fifteen years ago one might've been able to blame the PC monitor for accumulating static charge and somehow depositing it on you. Nowadays, with CRT monitors being history, there's no longer a realistic way to get charged by simply being in front of the computer.
As a comment says, it's more likely that you get charged by rubbing your clothes against the chair. I.e. even if you replace the computer with a paper book, you'll still experience the same effect (provided the book is as interesting as the computer has been :D). Strength of the effect, i.e. the amount of charge accumulated, should depend on the material of clothes (as you noticed), as well as on the material of the chair. There exist some antistatic chairs that may help you avoid this.
A: I am no expert in how computers exactly work, but I have read that computers release some radiation. It is nothing to worry about, it won't do any harm, but I think that may be causing some static charge in your clothes, especially since you sit in front of the computer for long times. That is why they make the sounds.
A: A computer screen can build up a static charge after a period of use.
If you are close to the screen, the charge on the screen can polarize your sweater a bit, producing a small surface charge on the sweater.  If you lean back, the depolarization might be causing the crackling.
