I just got my new Shimano 105 5700 shifters delivered. Got them out of the box, looked them over, and everything worked and looked good. Once I got the cables installed and everything clamped on the bars the B lever on the right (rear derailleur) no longer wanted to work. It will push as far in as it goes before it clicks. Sometimes it rolls the mechanism back, but most times not. The A shifter works fine. As I was trying to find the problem the B lever got progressively worse so that now it won't work even sometimes.
Has anyone experienced this problem? If so is it fixable or should I just send it back?
Bear in mind I have not fiddled with the mechanics, other than turning the allen screw located on the underside of the shifter by the clamp. (I thought this might be a trim adjustment, am I wrong?)