Something was beeping

Was it one of my fire alarms? Or the carbon dioxide alarm? I can’t change the batteries in the fire alarms, you need a latter. Wasn’t a very loud beep. Maybe it was one of my UPSes.

Update
It’s my PS4. It was in rest mode, looks like it’s off now. Might of updated itself and broke itself. If it turns on in safe mode, I’ll have to unplug it and wait 20 or so seconds and turn it back on. Appears to be fine, it was checking the drive though. Clicking noise when I turned it off. What file system does the PS4 use? I’ll replace the drive with a 500 GB SSD, Transcend of course.