Popping/Cracking Sound

I totally remember hearing something similar around that stage of my pregnancy with my girl, and I panicked too! I think what you are hearing could be the baby moving around in the amniotic fluid, or even your own joints and ligaments shifting as your body adjusts to the baby's position at week 36. Since you are so close to your due date, I would still bring it up with your gynae or pop by the polyclinic just to get peace of mind, because they can check properly and reassure you. You are almost there, mama, hang in there!