I've now been having a vaguely similar problem for a week, except that at first the power LED was continuously lit red, not flashing. Then the symptom morphed and now I randomly find the unit OFF, with no sign of life at all. The cause doesn't appear to be the AC adapter as you might presume, since all I have to do to revive it is unplug the power from the Obi110 and plug it back in (not unplugging the AC adapter, which along with router and modem is plugged into a UPS, BTW).
Is there a command that can be sent to the Obi110 to fully power it off? In other words, could this be caused by a spurious or deliberate packet sent to the Obi110?