I keep aspirating stomach acid in my sleep. what could this be?

LPR ?: Exposure of the vocal cords to stomach acid ; pepsin will result in inflammation of the vocal cords (as is also often seen with acid regurgitation) = lpr. Acute laryngitis may result, but watch out for chronic hoarseness, throat clearing, airway spasms, cough, bronchitis, an asthma-type presentation, ; even a higher risk of throat cancer. May however not be reflux so please get yourself checked.

Reflux: Sounds like reflux. You should speak to your doctor about treatment.