Just noticed that the dry winter air has done something to my Risa solid concert. The fret edges feel sharp and stick out. I haven't used a humidifier since it's an electric uke and I mostly keep it out of the gigbag anyway since I play it very often. Is there anything I can do about it? I'd hate to try to file the frets down since wouldn't that ruin the finish? As you might know there's no protective strip to cover the edges of the frets but the uke is made of stained maple and has a satin finish. I can still play my ukulele but the sharp edges annoy me.