It was the first stage- the hole in the top that I think is the overexpansion valve was popping for the prior dives but reset after I turned off the pressure but the last time the gas kept hissing out at high pressure.
I'll drop it off at a local regulator technician when I get the chance, I have more backup 1st stages and already swapped out the hoses so it's not an issue at the moment.
I had a backup 1st stage on the boat and everyone waited while I swapped hoses but when I turned on the pressure my 2nd stage was freeflowing heavily and I couldn't stop it so that regulator is going to the tech as well to check out the IP.