I know how frustrating it can be. I too have a sliding hiatal hernia. When it gets stuck in the up position I get so much pain. The ER told me on Tuesday that they could not see the hernia on xray but because I refused the dye their view was limited. That's crap if you ask me. They could see a lot on the xray but just love to use us as lab rats. Sliders are very hard to detect. We know they are there as we live in these bodies but unless they do invasive testing, they say they are not there. I too have a cough from the hernia which causes the silent reflux to creep up especially during the night. I sleep sitting up which helps, i don't eat 3 to 4 hours before bed, i take a gaviscon before sleep, my food intake is minimal and bland. Just not sure what can be done. I do not think surgery is the answer for me. It might be different for you. I would find another doctor if I were you until you get someone who will listen to you.