This morning my UPS complained about battery replacement, so I shut down the H340 using the power button, then replaced the battery in the UPS. The H340 power button is dimly lit in blue and when I press it, the red "i" light, the "USB Backup" light, and all the drive lights flash once, then nothing. Pressing the power button again does nothing until I unplug it and plug it back in. Any ideas? This has been working reliably for our family since we bought it new ages ago.