I have a very faint leak somewhere in the body of the valve, highlighted below, and can be heard down the barrel. I determined the location by putting my ear to it... I know, it's not very scientific but that's the best I got.
The leak is louder when the trigger is at rest, and quieter when the trigger is held.
It doesn't seem to be a carrier leak because neither pushing on the bolt nor reducing carrier sizes change the sound.
It started after I removed and cleaned the ULT on/off, described here. I first thought it was a ULT leak but after putting in new o-rings and eventually putting in a (RT) on/off, the leak persisted. So (I think) this rules out ULT leak.
(XValve explode view for clarity)
I have since changed/swapped out the following:
#27 - reg. valve pin assembly (just the o-rings, NOT the whole assembly)
#7 - reg. seat o-ring
#20 - reg. seat o-ring
#13, #20 - on/off o-rings (I've even swapped out the entire ULT with a R/T on/off)
#6 - L10 carrier (went down in size while retaining the same carrier o-ring)
The curent configuration of my LV 10 bolt is with 0.5 carrier and no shims, as well as an ULT with 4 ULT shims.
I am at my wit's end here... any help will be highly appreciated!