Hiccup Sounds (reverse hiccups)

I am 22 years old, and for the past 3 years I've experienced what my friends call "reverse hiccups" about   30-40 times a day. It's similar to a hiccup, except much louder. It often sounds like a gasp, and ranges from being quiet ones I can muffle to loud ones that stop everyone in the room. Sometimes I can feel it coming, and make it stop completely, other times it suprises me just as much as those around me. (Sometimes I can feel it coming, try to stop it, and it happens anyway). They can be extremely loud, and very embarrasing. They sound very odd, and I havn't met anyone else with anything similar/similar symptoms. I'm often accused by my parents / friends / teachers of doing it on purpose to 'try to be funny' or 'get attention', but it is honestly something I cannot control (beyond somtimes being able to stifle them).
I used to think it was related to stress, as it seemed to happen more often in certain environments (The first year it happened most often during classes/work, it now primarily occurs in social settings or when I'm talking to someone). It does not seem to correlate to or have any patterns to any foods, and I'm not experiencing any acid reflux (which is what my father now thinks it is now that he believes I'm not doing these on purpose).
Does anyone have any information? I asked my doctor about it, but she hadn't heard of such a thing and doesn't seem concerned.

[ve3avy]

I have exactly the same symptoms yet your post is the only one that was returned in Google.  My reverse hiccups started a good 10 months before the onset of severe Acid Reflux so I would see your Doctor any try to circumvent the inevitable.