ULT issues

I have 3 ULTs that are all confirmed to be the culprits of various issues such as short stroking, rapid fire trigger bounce, brief decaying leaking down the barrel with the trigger held down, and failure to fire depending on the number of shims used. Replacing the orings in the ULTs doesn’t seem to result in any improvement in function. Swapping the ULT on/offs out for an RT on/off eliminates all problems.

One of the ULTs started having problems (short stroking, double firing) a while back when the on-off pin had gotten slightly bent. Not surprising.

But both of my remaining ULTs seem to be having similar issues in addition to serious trigger bounce rapid firing, and worst of all, intermittent failure to fire where the trigger is spongy and pressurized, but non-responsive. Other times, pulling the trigger slowly results in a leak just before the shot, and multiple shots are common for a single trigger pull.

To my knowledge, the ULT on/off pins of the last two haven’t been damaged, but they’re sure not acting like it. I’ve been using these guys for close to 20 years now. Do ULTs eventually wear out? Or am I missing something here?