WHY DOES MY TOILET SOUND AS THOUGH IT FLUSHED ITSELF?

Typically the toilet douglas valve seal has become warped and is letting water leak out of the tank. The fill valve has sensed that the toilet has been flushed and is trying to refill the tank to its proper water level. No worries, it’s not a ghost, but it can waste thousands of gallons of water each year and is the number one source of water consumption in a home.