We have been suffering from Mystery Beep Syndrome for quite a while. It originates in the basement, can be heard in the living room, and is random in number and occurrence. It’s not a smoke, C02, electrical interruption notice, computer update, battery-powered device, cable device, and so on. I’ve combed every nook and cranny in the vicinity and there just isn’t any beep-producing equipment; it’s been happening for two years, so if it were a low battery warning it would have died long ago.
It’s a PG version of Chinese water torture . . .