When we play guitar, we want our notes to ring out cleanly and clearly. Fret buzz is the annoying buzzing sound a string makes when it's not properly fretted.
Fret buzz can be caused by:
Improper technique
A poorly set-up guitar
Fret buzz caused by improper technique
As a beginner guitarist, fret buzz often happens because you aren't applying enough pressure to a string.
This problem usually resolves itself over time as you gain strength in your fretting hand, but it's important to make sure your technique isn't holding you back if this is the case.
Tuck your fretting-arm elbow in close to your torso.
Curl your fretting hand, and place your fingers close to the metal fret
Fret buzz caused by a poorly set-up guitar
Guitars are made of wood, which means that they're subject to warping and movement based on the temperature and humidity of your room. With age, your guitar can become harder to play, making fret buzz unavoidable.
Here are some cases that may cause fret buzzing due to warping or wear & tear.
You need a fret dressing:
Metal frets can become uneven or worn down for various reasons.
In this case, you’ll need a fret dressing to fix the buzz.
A local luthier or guitar tech can do this for you.
You need a nut / truss-rod / action adjustment:
There are a few reasons that the height of the strings in relation to the guitar neck may be off and cause fret buzz.
If the strings are too close to the frets, you’ll have fret buzz regardless of playing technique.
If the strings are too far from the neck, it will be much more difficult to press hard enough on the strings.
You need to change your strings:
If your strings are too long overdue for a change, they may have built up a grimy film that contributes to fret buzz.
If you aren’t sure what’s causing fret buzz, and you're playing with proper technique, take your guitar to a trusted guitar tech for a diagnosis.