I've had this lanikai lu21T for about 3 months and i noticed that my C string had a very tin-like twang sound to it. So i took it to my local music store and they said that a fret was popping up so they hit one of the frets down with a hammer and oiled the bridge. Now 1 day later the G string first fret has that same annoying twang sound. I'm going to try to hit frets down but is their a better solution?