Every once in a while, well becoming more often, my low E string will start to unwind at the piece between the bride and the bridge pickup (Im not sure what that piece is called) why could this be?
What kind of guitar do you have? Do you have a tremolo system? What gauge/brand strings are you using? What tuning are you using when it happens?
When it unwinds it the center solid wire broke then the outer wrap just uncoils. If its at the saddle each time then there is a sharp place in the saddle.