[irvine]

I just bought a new guitar, went home with it, and wanted to make final adjustments, as done many times before. One thing was to adjust the neck bow. Took the supplied allen key and turned it anti-clockwise to loosen the truss rod. After approx. half a turn something cracked heavily. Now it is neither possible to tighten nor loosen, and move the neck in any direction. From what I can see, it seems it is (or was?) a double action truss rod, and the welding on one side might be broken.
Has anyone experienced such a fail with double action truss rod?
Was it my fault - with just half a turn loosening it?
Comments highly appreciated.