Bowel movement Why does the stomach of my 4months baby makes sound whenever he is breastfeeding?
Can you describe this noise?. Noise is not necessarily an indication that something is wrong. The sound you may hear is like a puff of air coming from the back of the throat, or "kha, kha," the sound of the baby exhaling after a swallow. If you hear that noise, it is a reliable indicator that the baby is swallowing.

If this persist, you might consider seeing a doctor