I’ve just started a vagus nerve stimulation device, Neurotrac Multitens at very low setting ( as recommended on ‘AVA: a vagus adventure’ Facebook group)…so far after 3 days only difference I am getting is popping of ears and more mucus apparent in nose/back of throat….the vagus nerve is supposed to be linked with clearing out ‘passages’, so I think this is what is happening. I’d tried NAC for many months a year or so ago, and didn’t notice any difference.