It must first be determined where the strings are breaking. Is it in the same place each time? If so and that spot is at either the agraffes or Capo bar I suggest restringing and replacing either agraffes and /or resurfacing Capo bar. This should cure your problem. I had a Kawai gs-70 with the same problem and restrung over 6 months ago and no strings have broken since. There were always several broken at each monthly visit and it wasn't from playing hard. Try it you'll like it!
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