On the bench today I’ve got a 2008 Gibson Les Paul Studio that’s been driving its owner nuts: fret buzz, weird noises, and tuning instability. In this video I walk through how I diagnose a problem like this step-by-step, starting with the basics so I’m not chasing ghosts. I check neck relief first (I like to see about 0.006–0.008" at the 7th fret), then I set the action to something reasonable before I blame the nut or the frets. From there I measure string height at the bridge (Gibson spec is 5/64" bass and 3/64" treble, but I generally aim for 4/64" across), and I also lower the pickups because overly high pickups can add their own weirdness. The big red flag is nut action: several strings are effectively sitting on the first fret, and even a 0.010" feeler gauge won’t slip under on the D/G/B. That points to nut slots that have been filed too low over time, which will absolutely cause open-string buzz and can contribute to tuning issues. I also find a high 3rd fret with a fret rocker—another classic “you fixed everything and it still buzzes” problem. My diagnosis: replace/reshape the nut for about 0.016–0.018" at the first fret and address that high fret (press it back in or level/recrown).