I hear crackling in the back of my head/ears.
I really can't tell if it's coming from my head or my ears, but I've had this symptom for as long as I can remember. I can cause the crackling noise without even moving my head. It's hard to explain how I do it, as I don't even really know how I do it. How would an animal explain to a human how he moves his tail, if he knew how to speak, that is. All bad metaphors aside, I have no idea what it is, and have gotten used to it by now. I have never told anyone, mostly because I never thought anything of it, but now I want to know why I have it. Also, my neck cracks when I just turn my head to the side, and it doesn't sound healthy.
Other things you should know: I broke my back when I was in 3rd grade. I may have had the crackling before that, but I can't remember.