I have the same clicking sound! I am a 42 year old male.
In order to make the click happen, all I need to do is say a 'k' sound, and then "snap" Sometimes it's soft, sometimes it's loud, and sometimes it doesn't happen at all. It doesn't cause any pain, the problem for me is that I am professional actor and Voice Over actor, so this is literally preventing me from doing my job when it happens.
Here's what I've noticed: If I make the 'k' sound and relax, snap. If I make the k sound while opening my mouth wide, and keep my soft pallete up, without relaxing it, it doesn't click until I relax my soft pallette. Then as soon as my soft pallete drops, click! I've tried doing it with absolutely no movement from my jaw, and it clicks just the same.
My ENT said it was a large strand of mucous that was snapping when my mouth moved a certain way . I was BAFFLED that he had absolutely no suggestions on how to get rid of it (as I had already tried Mucinex and it did nothing). He also said I had reflux and prescribed a reflux medication.
Again, this sound prevents me from doing my job in many circumstances.
He said it may be allergy related
I've tried nasal rinses, several allergy medicines, mucinex, and blowing my nose a lot. Nothing seems to work.
Is this the same thing you other guys are having, or is it different?