For new installs if not satisfied with results, 1st try adjusting string tension. Next try rotating unit slightly. If results do not improve after this, we strongly suggest trying different locations! If you have had your harp for several years, it may be necessary to replace nylon strings(your harp will work missing 3-4 strings). Usually, once a string or two breaks, it is time to replace all of them. We sell them through our site, instructions are included. We also sell screws with nuts if you have to replace them. For issues with finish of frames, please sand or wire brush away any rust, then touch up with good outdoor enamel.