Do you take in chocolate or coffee? If you do try cutting them out completely (yes, agony I know) for a month. Have you tried googling for all things that weaken the esophageal sphincter? There's a list of foods that do this. Also did they rule out hiatal hernia when they did your tests? I've have problems with acid reflux mainly triggered by coffee and chocolate, dark chocolate is the worst - it's a shame because I love those foods above all.