I have a JTV-69 (Korean) paired with an HD500x and the acoustic models are giving me a major issue w/ the sound when hitting certain frets. Typically the string/fret that make this noise is A-7&8th fret and also D-4th fret. The sound is almost like a feedback and horrible resonance sound where the sound is much louder than the other frets. Anyone else notice this issue with the acoustic models.