I hadn't used mine (5072P running 5202p firmware) for about 12 months, and when I switched it on, it kept rebooting. Occasionally it would show that same system update page, but eventually, after about 50 reboots, it stayed on, so I left it running for 10 minutes, then downloaded the newest (25/01/2019) 5202P firmware from the Hantek website and flashed it, ran the self calibration and it seems fine, but I'm guessing there's most likely a dodgy cap on the power supply. Might be worth a check.