I've had a small APC 500 VA UPS in my bedroom for almost 5 years now. The only things plugged into it are my old cathode-ray tube TV, VCR, and DirecTiVo DVR. At 4:30 a.m. Wednesday, I hear a loud, single BEEEEEP. I'm looking around and see that the VCR clock has lost power, and the DVR green light is on, meaning it has to be rebooting. Translation: the UPS lost power momentarily, even though it is plugged in and there was no power outage. That night, I install the UPS software on my computer and connect it to the UPS in order to disable audible alarms. It says that the battery is fully charged and could run for 49 minutes, which is fine because I installed a standby backup generator this winter, which kicks in after 10 seconds of no power. I reset the VCR clock. The next morning at 5 a.m., BEEEEEP (despite disabling audible alarms the night before). VCR clock out, DVR rebooting, with the UPS plugged in and no power outage. I get up and see that the UPS green light is on, as it should be. What gives? I come out of the shower at 7 a.m. and see the DVR is rebooting again. That's it. I unplug and disconnect everything. I can't have the UPS bothering me in the middle of the night and the DVR rebooting again and again when the UPS cuts power. I ordered a new UPS but keep wondering how on earth could this possibly happen? The UPS was plugged in, the green light was on, there was no power outage, and the software said the battery was fully charged with 49 minutes runtime available. Yet the thing beeped and cut power to my VCR and DVR two days in a row. Is it defective? Is this common? Has anyone ever heard of this? I can't find reference to any similar problem on a Google search.