One night my son was playing a computer game while I was watching TV. I asked him to turn the sound down, and he did. After a short while he came over to watch TV with me. Every so often I would hear the engine noise of his game. I asked him to turn off the game. He did. I was still hearing the noise and told at him to turn it off. He said he had switched off the power to the PC, but I was still hearing the engine noise about once a minute. We went over to look. Sure enough, the computer was off, but the sound was still there. We unplugged the speakers. Didn’t help. We pulled out the batteries. Didn’t help. Then I realized it was my pager that had been sitting on one of the speakers.
