I have been running into an issue with Rean (Chinese division of Neutrik) RCA's, where the ground is fouling out and losing connection. Below I'll show my fix for the issue.
Connector out of the package
The pen is pointing at the spot of the issue.
Here I've bent the strain relief tab to exaggerate the issue. As you can see the strain relief tab is not physically attached to the shell, it's a pressure fit, where they crimp the shell to the tab, which is common with a lot of RCA's even Switchcraft, but I guess they don't use enough pressure at the Rean factory.
And here's the fix, when you open the package, bend the tab down just a hair, just enough to see a gap between the tab and shell, then you'll want to solder the two pieces together. Leave your iron on a little longer than you normally would for a connection, this will heat more of the metal, drawing the solder in further and making a larger surface area of contact.
And that's it, continue on as usual.
I personally no longer use Rean RCA's, but I figured I'd provide this information for anyone who may have a stash of them that they'd like to keep using them.