Problem with sound of power chords
Your strings are too close to fretboard. But first of all You need a tuner. Don't play without tuning Your guitar. Check one of these
I'm not sure it's "buzzing" what you refer to.
1. your guitar is out of tune (just saying)
2. to weird sound that you call buzzing can have 2 reasons.
First: string being too high above the fretboard and you simply don't press hard enough for it to reach it. It's typical for beginners to have problems playing chords with high action.
Second: "buzzing" is when your strings are too low and after you play it instead of vibrating in the air they are touching the fretboard.
I'm pretty sure in your case it's high action, but I may not have heard it well. Either way, check your action. If it's okay - then make sure you are pressing the chord well.
Your sound could be a lot worse, but make sure your fingers are forward in the fret space - close to but not touching the fret wire
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