KJS: I know this is obvious, but I have to ask: Did you check the strain screw? I have an acquaintance who had a new 686 SSR. Fired several hundred rounds through it - ran 100%. Took it to an IDPA match, first time up on the line -bang, click, click, click. The strain screw had backed-off 1.5 turns. Cranked it down and we were at 100% once again. Check the strain screw and if it has backed off, a drop of purple Loc-Tite will keep it in place. Hope this is all it was.
Adios,
Pizza Bob
PS: This really should be in the 1980 - Present Forum