Hi all, i've been bought a second hand 5 string left-handed '03 streamer jazzman, wonderful instrument, but i'm in trouble with the truss-rod, it's come with a big neck relief, about 5-6mm at 12th fret, ok, i'm going to tighten the rod but here start my pain. First, the rod it's very hard to rotate in both directions, i'm going to turn clockwise and i've hear a cracking sounds to the neck, no reaction in bow. Some hours after, i've noticed a headstock twist, ca 2mm in difference counter-clockwise. I've restored the rod in it's original position and seems the things are returned to normality. Can I do anything to adjust the neck? Help me please.

