I don't think mine have been as loud, but I've gotten some good cracks and crunches from C0 - C2. My 2nd chiro who uses "the Activator" tool diagnosed me with upper C problems. After reading about them, I agreed. I see him weekly and my neck and head alignment has improved substantially. My head used to be visibly tilted (towards the TOS side, of course--the vortex of badness).

Make sure you are not in forward head position, even slightly. Also, consider adding "Fixing You: Neck Pain & Headaches" into your self therapy routine.

Good luck.