This started a week or so ago. It's a quieter sound than, say, cracking a knuckle on purpose, but maybe similar to how it sounds and feels when a smaller bone in your foot cracks when you are just walking around. It just seems bizarre to me. I can't really identify *what* is cracking, just something in the general hip/pelvic area. Anyone else? I'm not worried about it, just sort of surprised and baffled.