Why does my guitar buzz when I use a capo? If your guitar buzzes when you use a capo I would venture to guess it also buzzes when you play with out the capo. Buzzing occurs when a vibrating string is hitting another fret, or residual vibrations in the guitar cause other loose components to rattle/buzz. This can happen quite easily with acoustic electric wiring and hardware that had become loose over the years or was not installed correctly.

If it is loose wiring or components the fix is quite simple, tighten things up. Make sure all of the mounting hardware is tight and all of the loose wires are bound. In some cases it may even be a battery vibrating against an internal wall. In cases such as this one can simply wrap a shim around the battery so it doesn’t have any room to move. Be sure not to use a conductive material.

If on the other hand the buzzing is coming from a string hitting another fret the fix is a bit more involved. The easiest thing to do is to bring the guitar to a luthier and have them take care of it. They have the skills and tools to dress your frets, correctly adjust your truss rod, or make any number of other adjustments that may be required. It is a good idea to bring your guitar in every so often for this any way. Like a car your guitar if used regularly will need a tune up.

So the short of it is that it is not the capo that is causing the buzzing, it is the guitar.