1 Min- High Pitch Noise

I just want to know if anyone else in this general area heard anything. Or saw/experienced anything like this.  This has happend before many times. (Different situations). A strange high pitch noise came from our computer room. Computer was on but I was not in the room. I often stay up late on my computer and have never heard this from that room before! Within seconds after it started and then a loud low flying fast (aircraft) went over.  But the strange thing is, the  high pitch noise shut off one minute later.  Like a switch.  I was not tired before this but suddenly afterword overwhelmed with exhaustion to where I could hardly write this down on paper. I often stay up alot later then this! But the (airplane) engine or humming sound one makes never ceased completly! I can still hear it an hour later, its not as loud but its still out there!