My stomach gets very noisy too. The muscle contractions that move food through our stomachs is still happening but now there is only gas pockets/liquid to move so we notice it more (the food isn't breaking up the gas pockets).
Another think to consider with bloating is that VLCDs can change your menstrual cycle so it may be that. Also consider constipation which will trap the gas further up in the abdomen.... some fibre from the CDC may help.
Take care