Hello sevenstring community!!! Well, I am a new user and I have been playing guitar for 2 years by myself. Yesterday I changed strings on my Gibson Flying V, tuned up to standard E and went to check it out, only to realize that the high e (1st string) gives off an unwanted feedback, like a "sitar"/echo noise, when I play several middle frets together (frets 4-8). This happens when I play several notes, not one only. I checked my tuning, intonation, truss rod, action, pickup height, etc, etc, anything that came to mind. Those seemed fine. However, later that day I noticed that the high e plays perfectly, no echo/sitar like noise or any type of unusual feedback, when the other five are not in tune. Whenever I tune up strings 6 through 2, the high e sounds like that. What's happening here and how can I fix it?!!