I have a Volktek INS-802 Power Injector/ethernet switch that has lived in my attic for the past four years or so that's started giving me problems.
At first it the access points attached to it started bitching about not enough power, then it would post but give some sort of alarm (I'm not sure what that was since I've never been able to set an IP address without it resetting with a power cycle, not that it was a problem), and now when I plug it in it goes into some sort of boot loop with a relay clicking.
This poor industrial poe switch has had a hard life, first coming from some mining company in alaska, and then living in a hellish texas attic. Still all within its rated capacity.
Anyway, I'm going to tear into it soon and see if I can figure out the problem. I thought I'd go ahead and post here and post more information as I start tearing into it.