aswander

I'm thinking GERD - gastro esophogeal reflux disease. It isn't always accompagnied by heartburn. If your upper esophogeal spinchter is weak, some acid can escape the esophogous and get aspirated into the lungs.

But you may also be one of less common individuals who has the classic weak lower esophogeal spinchter muscle yet no heartburn, and acid is flowing into the lower esophogous. This is escpecially dangerous, because you can develop excessive damage without having had any of the classic heartburn symtpoms that would have led someone else to get treatment earlier.

The point is, the next doctor you need to see is a gastroenterologist, who may place you on Proton-Pump Inhibitors to reduce the amount of acid in your stomach. They may also recommend an endoscopy.

Since you saw an ENT, did the ENT "scope" you? That is, did he insert a thin wire with a camera at the end up your nose and down your throat? If he didn't, have him do so to check for redness and swelling in the laryngeal area.
That is also treated with Proton-Pump Inhibitors.