Macs waking up when other electrical devices are powered on or off

We continue to cover a phenomenon where other electrical devices on the same circuit as a Mac could cause that computer to wake from sleep when they turn on/off.

We've since received additional confirmation of the issue.

One reader writes "I believe this problem can be connected to static discharges in the room. During the winter when the air is really dry in my house, if I get out of bed I will hear static in my comforter discharge and then my Mac will wake up. I have even had this happen when turning on my TV which is on the same circuit about 6-ft away. Some macs have a "touch" button that can be activated by just making contact with them. I assume these are based on capacitive properties. Static buildup in a person is basically the same principle that capacitance works on thus when you touch a switch or discharge static electricity it seems possible that the mac mistakes it for a user trying to tell the mac to wake up. I have been using a humidifier to keep the static down and it has seemed to end this problem.

Another reader, Hib Halverson, adds:

"I've had this problem for a couple of years with my G4 1.25GB desktop. Currently I run 10.3.7, but I've had the problem since I switched to X with 10.2x.

"If the machine is sleeping and I run the microwave or the toaster in the kitchen which is adjacent to my home office, sometimes the desktop will wake from sleep. This happens inconsistently but on a regular basis.

"The computer and its peripherals are on one side of the kitchen and are on the same line coming from the house's electrical panel. What's interesting is this desktop machine is connected to household service through a UPS.

Feedback? Late-breakers@macfixit.com.

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