I have one of the above, been maybe 3-4 months now, and the solenoid just gets louder and LOUDER! This morning it sounded like a numatic drill going through a brick wall! Then I just turned the power off and on a couple of times and it became a bit more quite. Though it used to be silent, and is now still pretty loud. Does anyone else have this problem? It's REALLY annoying having that buzzzzzz all the time!