Hi.
I’m using RB4011iGS+RM about 1.5 years. In ether10 attached Unifi CloudKey Gen2. Mikrotik is powered by Mikrotik 48POW, in Health showed 48.2V, temperature is 44C.
After a reboot a few days ago CloudKey stopped receive power from ether10. I see poe-out-status: powered-on, but there is no current on ether10. 4011 “sees” the load on port (when PoE-out=auto it changes status from “waiting for load” to “powered on”). CloudKey works properly from another 48V injector.
Tried to update packages and firmware to 6.47.10 and 6.48.3, but it did not help.
PoE-out is dead? 
Check your Layer 1 ( your cable connected to the PD (Powered device) )…
Forgot to write… Tested with 3 different cables.
This topic is about powering 4011, but not powering from 4011. My 4011 is not powered from 802.3af/at, it powered by Mikrotik 48POW in DC-Jack. And my setup worked for 1.5 years, then stopped after reboot.
Test if you can power another POE device from your RB4011…
I have same problem. My PoE out died in port 10
Same, worked for years powering a hexS, then died after a reboot. Quite peculiar that it died during a normal ‘soft’ reboot. The power was not removed. Port 10 works as gigabit ethernet, goes from ‘waiting for load’ to ‘powered on’ but provides no power.
I also had one where POE out just stopped working after a reboot. And another one where the LED’s on the POE port stay lit regardless of what’s plugged into it.
It’s possible that they just have poor surge suppression or weak power transformers or something that causes them to randomly fail.
Not entirely related to the POE out problem, but just last night I had a separate one where all the ports on the first switch (1-5) dropped their link. Manually bouncing the ports didn’t do anything; I had to reboot it to get them to come up. And a few weeks ago, after attempting to upgrade one, the upgrade failed and I had to swap it out. Fortunately a Netinsall fixed it, but it was nerve-racking nonetheless. I upgraded two others just fine the other night.
As solid as 4011’s have been for me in the past, it seems they do wear out. At their price point, there’s no reason not to keep a spare handy.