Any foods you consume regularly??
I found out the hard way that coffee gives me the same symptoms you describe. Real bad. I just had to completely quit coffee. Can't even touch a sip.
Anyways, valium and other benzos will give you hiccups which can also give you acid reflux. I would say lay off of those.
If it gets really bad, lay off all drugs especially steroids/nsaids for 3 weeks except for a double dose of prilosec and tums/something like tums as needed. Also only stick to whole, easily digestible foods during this 3 weeks such as oatmeal, chicken breast, etc. Also do not drink anything but water. If this doesn't get rid of it, you may be in real trouble.