Noel, please replace the existing paragraph with the following modified paragraph in .... &gt;Tech Support &gt;Adjust &amp; Setup pageYou can explore from a low pickup height setting with a high volume amp setting OR with the pickups at maximum height with lower volume amp settings. Some players prefer one or the other and some prefer in-between so PLEASE experiment and try both approaches. -and- Dirty or rusty strings can also do this but many players know this horrible phenomena is caused by excessively strong magnets in the pickups, here's how it works. What happens is the magnets of the pickups pull on a section of the string (the part that's over the pickups) into a U shaped vibration path. Normally the strings vibrate in what is essentially a single-plane path or pattern that is more or less straight (not U shaped). Lets say that the time taken for a string (not subjected to excessive magnet pull) to complete one cycle or oscillation is X milliseconds (this is the pitch of the note). Traveling in a U shaped path it actually takes longer to complete one cycle or oscillation since the distance is greater via the U shaped path, so the time is X + Y milliseconds. Now it's getting clear that what you have is a string that has a section of it's length vibrating in a U shaped path and part of the remaining section traveling in a straight single-plane path and yet other sections traveling at all frequencies between these two extremes.