I've had a takamine 12-string for a few years, and I've recently had a lot of frustration when it comes to restringing it. As soon as I get to the secondary, higher g-string, and attempt to tune to concert pitch, the string just snaps. Doesn't seem like too big of a problem, it's just that within the past few hours, I've gone through 3 sets of strings, and I still don't have a high g-string. Any advice? I've tried light and extra-light gauges, but neither get the job done.