I just got this head and it might have a problem...the pan and tilt knobs have both an outer collar for tension and an inner knob for locking. On mine, the outer collar for the tilt knob doesn't seem to turn very easily and when it's at maximum tension, the tilt is still pretty loose. I think it should be able to turn further. I can turn the PAN outer collar more than 2 full rotations, but for the tilt I can only do 1 rotation and that's by forcing it. It's almost like a screw misaligned on the threads. If somebody has this head handy, can you let me know how many full rotations you can do on the outer collar of the tilt? Thanks. And also any advice on how to fix this would be appreciated.