I am so sorry you are miserable! I was never actually formally diagnosed with IBS, but the only thing that helps my belly is prednisone, for whatever reason. My stomach is calm AND quiet as long as I take about 10mg per day. Otherwise, you can hear my noisy stomach from across the room, especially after I eat.
I would make an appointment with a GI doc and have some tests done if you have not already. All of mine were *normal* so it is hard to say what is wrong with us sometimes.