It appears my response to your post didn't (yet) show up. I'll try again.
The couplers are roughly two years old. They're EC87K. I've got two packages of six that I was intending on working on. I've only assembled the one, as it seems wise to put assembly on hold for awhile.
It's good to hear that the bad ones are being replaced. I'd sure like to hear more about that. From Frank. As in: the protocol.
I did read through the "stuck open" archives, and it appears none of it relates to my problem. Or perhaps "our" problem, as I mentioned others appear to be having a problem, also.
I look forward to a solution to this problem.
Thanks for the guidance,