Why is there constant grumbling noises coming from my bladder?

Probably the guts: It is unlikely from your bladder unless it has a fistula. It is more likely from your intestine. See doctor if you have discomfort or feeling ill.

Intestinal noises: The bladder is located just above the rectum--terminal end of the large colon . Intestinal noises may be described as growling,gurgling or even rumbling. These noises are medically known as borborygmi and are various types of intestinal noises caused from the movement of food and chyme through the intestinal tract as the muscle contraction of the intestinal wall mixes an and breaks down the food