Thanks all,
Well - doesn't sound too good does it :-\ It does look somewhat illogical as to how it's supposed to hold the string in place with the ball the size it is for the G string. It's still under warranty so maybe I'll get it looked at :-). This is how it came from the shop.
Colin.
PS It does look like maybe some of the casting has come away due to the tension on the string. Anyway I have email the place I bought it from. Cheers all.