Pete writes:
I recently bought a '79 Fender strat - it was a bit of a mess - so I took it apart and cleaned it out. When I put it back together, I noticed it was 'splitting notes' higher up on the bottom E string (when playing one fret, two notes sound). What could be the cause of the problem?
This is an issue that I've run into myself quite a few times. The problem generally is that the pick-ups are set too high (too close to the strings), and the magnetic pull from the pick-ups changes the natural vibration of the string. For more info, see this:
Pickup Height on your Guitar: How Close Is Too Close?