Indeed, I think the UPS has a problem. See if it can be repaired. If not, and you need one, you'll need to buy another one, I'm afraid.
Okay so I've got a UPS (on the back it's written "Mercury" and "Model: Elite800 Pro" and everytime the power goes off my ps4 instantly shuts down after the ups lets out a single long beep.
Moreover, I tried to unplug the UPS cable from the wall myself to see if it does the same thing but instead it just instantly started beeping fast and shut down (could the ps4 be using too much power or something)
Do you think the UPS has a problem and I should get a new one?