Quote from OP's link:
Phase 1 & 2 - Cranium Clicking/Screeching: A phase 1 side effect goes back as early as 2001. Exactly what is happening is not completely known but involves some sort of nano-chip being installed/operated in the cranium (your head) of the host. This is probably the equivalent of a CPU of some sort. The actual clicking/screeching sound observed is usually at night on average once a month and only lasts for a few seconds. Completely painless and easily ignored or passed off by the person. The entire purpose of the movie Shutter Island (2010) is to discount this. The nano-implant that is specifically and clearly responsible for this side effect is symbolically referenced in the second clip for Surrogates (2009). I suspect over time they have improved this side effect.
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I actually remember this happening to me, although I'm not convinced it was from the process noted above.

I used to have brain crackling, it was painless and didn't seem to affect me. doesn't happen anymore, I'm 39, remember it happening up into my 20's at least.

I'm not the only one: [link to www.steadyhealth.com]