We have been seeing a lot of guitars coming in for adjustments lately due to action problems, buzzing strings and warping necks. These issues are all due to humidity control for the guitars. A lack of humidity in the air due to changing temperatures, not using a guitar humidifier, changes in altitude and improper guitar storage where temperatures fluctuate, can cause these problems to occur. Guitars are made of wood which expands and contracts with temperature and humidity changes. The wood expanding or contracting can cause action problems or even bow or warp the neck of the guitar. This same effect can also happen to other wooden acoustic string instruments such as violins, violas, bass, cellos and ukuleles. To prevent this from happening to your guitar, keep it humidified with a guitar humidifier and be careful where you store it. Wooden instruments should never be stored close to areas where extreme temperature fluctuations can occur. For example, by a heating/cooling vent, radiator, radiant heat, stove, windows or doors. If you detect a change in your guitar's handling or notice warping, bring your guitar in to an experienced luthier for immediate attention.