I noticed a buzzing sound coming from my speaker earlier today. Tonight, I decided to see if it had a pattern to it, and it does. I suddenly hear what sounds like an electronic drilling hum for about 15 to 20 seconds, and it happens every five minutes. I disconnected my speaker wire from my computer, and the sound was still coming out of the speaker. The speaker has its own power supply, so I am assuming that somewhere nearby someone is powering up a device for approximately 15-20 seconds, then it stops for around 5 minutes. I've been actually clock checking for the past 45 minutes.... On at 11:38:15 seconds, off at 11:38:33 seconds.... it was exactly every five minutes for a couple of cycles, then it slowed just a bit and now it is starting at around 12:28:30 seconds, off at around 12:28:45 seconds. I have to have my speaker up all the way. There is nothing where I am at that goes on and off every five minutes. The next one should happen at 12:33:35 seconds. (west coast time). sun of a gun, right on cue, at 12:33:34 seconds, off at 12:33:54 seconds. creepy stuff. I'll wait to see if it happens, then submit my post.