Triumph eXT not firing...sometimes

When i pulled the trigger, nothing happened, pulled a few more times, still nothing... again, and it fired

I replaced the battery, thinking that may be it, but this continued to happen.

I had to replace the rear bolt o-ring and I think I put everything back in place correctly, but not really certain where to check for issues.

When i take the handle off the gun, the trigger consistently fires (it clicks and what i assume holds the bolt back drops down, which should release it)

i can cock it back just fine and it will fire, the pin gets reset and looks like it's good again, but when i try to fire, nothing.

I have found that if I apply a little bit of pressure backwards on the cock-pin it will fire again, so, I assume something isn't 100% lined up, but I'm not sure which part it could be

Thoughts?

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EDIT

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editing in hopes of avoiding a bump, but..

for those that read this and care or have a similar issue... My buddy suggested that the solenoid may be gone... we took one from another gun to try to use it, but when I was removing the solder from the solenoid on the eXT, one of the wires on the capacitor just kinda broke (as i was holding the board in the air, only gravity being applied to the dangling parts (haha, dangling parts...))  

I was in a grumpy/half drunk mood when I was doing this, so, I half assed it and gave up before i could actually fix the gun, but at this point, I'm assuming the issue was a deteriorated wire the capacitor. 

Good luck to anyone else having this issue.