Abby, It could be a problem with the epiglottis. Or the glottis. You'd think there would be a post-glottis.
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An ENT doc could do a little office scope but, if it's a muscle weakness issue, that might make it worse. It made me worse when I had it done. They spray numbing solution into your throat to have a look see.

Not exactly helpful to paralyze the muscles you can't use very well to begin with.
Are you having any trouble with breathing at night? Have you had a sleep study to check for apnea?
Well, those are my thoughts. I hope you figure it out.
Annie