On my 2002 Lakland Skyline JO four string, my G string buzzes on the 7th fret only when the E string is fretted as well. I noticed this when running up the G scale with added thirds and it doesn’t happen anywhere else on the neck. Only the 7th fret D on the G string when the E string is also fretted at the B on the 7th fret. Bass was recently set up a few weeks ago by an experienced tech, whom I trust, with DR Hi-Beams. Haven’t noticed this until today. I recently also added a large humidifier to my guitar room if that makes any difference. Any ideas here? Should I raise the action? Edit: Could this be a frequency thing? No other note on E, A or D within reach causes the sharp buzz.