Inconsistent action and obvious string buzz may be indications that a neck is out of adjustment. Neck adjustments must be done accurately for proper action, intonation and fretting. This is done with strings tuned to pitch. Use a capo to press the strings to the fingerboard at the first fret while using a finger to press the low E string to the fingerboard at the fret at the neck/body joint. Measure the space with a feeler gauge at the 8th fret. The space between the string and the fret at this area should be no more than .020”. If this space measures more than .020”, the truss rod should be tightened in 1/4 turn increments until the space measures within this range. If there is no measured space between the fret and string, the truss rod should be loosened (counterclockwise) in 1/4 turn increments.
It’s wise to allow a few minutes for the fingerboard to settle after an adjustment (before measuring again). Personal playing preference will dictate the ideal/exact measurement for each player depending on musical style, playing dynamics and other factors. Neck adjustments should not be attempted unless you are comfortable doing so. Please consult a qualified repair specialist if you do not know how to properly adjust the neck.