David; I, too, think that the bridge is misaligned, but I'm not sure how that would be fixed. I've had no experience with ball-end strings but would think that moving the bridge would create a wide gap in the face of the guitar, one that might allow a ball to wallow around. It might be better to change the bridge from ball-string to string tie???

Kray; As my response to David indicates, I think the problem is at the other end of the fret board, at the bridge.