Gas Restrictions on decent

[Alaskan Scuba Dude]

Try descending feet down, head up while equalizing.

 

[Norwegian Cave Diver]

Problem must be in the…
First Stage - relocate the hose to a different low pressure port.
Primary Reg Hose - inspect the hose to see if it bends/folds over easily anywhere or has any visible defects to the surface. Feel the hose for any soft spots.
Primary Reg. Swap the Back Up Reg with the Primary Reg.
Only do one of the above and wait for the problem to happen again.

Good luck

 

[Angelo Farina]

Unfortunately I think the problem is not with the regulator, but with the airways.
You should search for medical advice. Here on SB there are some medical doctors who can answer better than me.
I have only some second hand info, so do not trust me too much.
But from this second hand info, what happens to your wife looks like a broncospasma (I hope that the greek-derived term also works in English).
In practice under some conditions the airways do restrict (spasma means contraption).
I have no idea what's triggering this...

 

[happy-diver]

It's there like a headless chicken, now those that come across your thread are exposed to clearer understanding

Win win!

If that's my only mistake for typing this up on my phone... not too bad