It could very well be gunk that has settled in the pivot screw pockets or key rod/tubes of the parts in question.
Does this problem go away temporarily when you oil these areas? If so, that may be the source rather than the springs or spring tension.
Did your horn take any knocks in that area recently? A bent rod or kink in the rod/tube, or a key rod post that has moved off center could cause an issue such as this too.
Does this problem go away temporarily when you oil these areas? If so, that may be the source rather than the springs or spring tension.
Did your horn take any knocks in that area recently? A bent rod or kink in the rod/tube, or a key rod post that has moved off center could cause an issue such as this too.