In Sept 2015, my sleep started to be disturbed by an on-off low vibrating/electrical sort of sound that *sounded* as if it was coming from the house, or outside the house, ie definitely not within me! To summarise the Autumn...disturbance to sleep affected my life dramatically. Checked everything - heating/plumbing, water, phone/electricity wires, aerial - and many more things, to try to find the source of the noise. Noise comes 'on' for a few seconds, then go off. Sometimes there every night for ten consecutive nights, sometimes not there for weeks...no pattern. Unbelievably, really, it took me six months to find out that if I take a sharp intake of breath, the noise stops! Then returns... (Only conscious of it at night). It doesn't sound the like the noise of my breathing - it's just as I describe at the start of this post. (It's not 'pulsile') Please, does anyone else suffer from this particular sort of madness?