I just saw these posts as I was googling trying to find some relief. I have been having the same problem for years and it has effectively ENDED my successful singing career. It's gotten to the point where I can no longer sing Happy Birthday or sing along with the radio and I feel like I am missing a limb.
Allergists said I have asthma and gave me all kinds of medication which did absolutely nothing but make me jittery.. I stopped taking them.
Gastro said GERD... I take Nexium and it is under control so no issue there.
I am at my wits end with this. I see this thread is not a new one. If anyone has found an answer or relief, please post it.