This has been a known issue as there was a Product Safety recall announced in Australia in July of this year. I wonder why Aqualung delayed to inform US customers for over 2 months.
Aqua Lung Australia — Aqua Lung Core ACD Yoke (all models), Aqua Lung Legend ACD Yoke (all models), Aqua Lung Titan LX ACD Yoke (all models)
Upon receiving the announcement, the tech at my LDS went and checked the Legends that were new in box and found one where the ACD assembly was so loose he could turn it with his fingers.
I wonder if this was the problem reported in this thread...
1st stage of regulator failed in close position - new diver freaking out a bit :)
I dunno. I experienced the failure this recall talks about, but thankfully above water.
This was 2 years ago, with one of the E serial numbered legend regs.
New legend, perfectly fine for about 5 or 10 times.
Last tank it survived, was put on a tank at 3100psi (IE well within limits), dives fine.
Go to set up for another dive. Put regulator on tank, it couldn't hold pressure. It was like a pressure relief valve was being tripped continuously. Happened repeatedly no matter what tank pressure.
Get home, send it off to service tech, who tests it on tank, see same thing happen. He disassembled it and calls me and says "there is nothing obviously wrong with this reg, at all". He was completely flummoxed. He reassembled it, worked fine ever since.
Since the recall requires torquing everything to spec, i bet there really wasn't anything wrong with it other than not being torqued to spec.
At the same time, quality control not catching torque spec failure for literally years seems ... bad.