I went to a call 2 months ago for a "whooshing sound" that the customer thought was water leaking in his attic. I arrived[ sunday morning ] and the house was dead silent so I naturally heard this faint sound. I walked up this loft area to the attic where the sound was coming from, looked inside and the was no furnace or fan coil. I came back out and heard the sound perfectly, looked down at a rock shaped speaker where the noise was coming from, so I put it to my ear and it was some type of weird radio static. So I turned off his radio for him. The guy was so embarassed but I still had to charge him. Everyone laughed for weeks after that one!!!!