Finding gas leak

I have read a ton of threads on here about finding gas leaks and regulator gas leaks, but I am still not able to find mine.

I recently added the dual secondary regulator from beveragefactory model T1672ST. I started loosing gas and sprayed everything over and over and I cannot find any bubbles or hear any leaks. I noticed one of the regulator gauges was holding steady at 12 psi, but the other was dropping. I disconnected that regulator from the keg, shut the valve, pushed it up to 30psi, then turned off the gas. After a few minutes, that regulator gauge was down to 20psi and the other was still holding at 12 psi. I sprayed star san on everything, held the keg gas connector under water, and I still do not see bubbles. The only thing that I notice that is bothers me, is the shutoff valve for that regulator is loose. The valve handle screw was loose when I got it. I tightened it and that did not help.

Any help would be great.

 

The far left regulator is the one that is loosing pressure.

 

If you have convinced yourself that the recently added reg is at fault, why not contact the Beverage Factory for an exchange?

Cheers!