Amazing, why didn't I think of that. You are absolutely right, when I wrote my post I meant the switch was doing absolutely [no switching], an AP was still connected with PoE. And the name of the process [PSED] could easily be related to something with "Power...".
I did the command <display poe pse> and this is what it said:
PSE ID : 4 Slot No. : 1 SSlot No. : 0 PSE Model : LSP7POED PSE Status : Enabled Power Priority : Low Current Power : 3.6 W Average Power : 3.6 W Peak Power : 5.2 W Max Power : 370.0 W Remaining Guaranteed Power : 310.0 W PSE CPLD Version : - PSE Software Version : 145 PSE Hardware Version : 57633 Legacy PD Detection : Disabled Power Utilization Threshold : 80 PD Power Policy : Disabled PD Disconnect-Detection Mode : DC
So it seems it's version 145, I will check if that is the latest one or not.
Thanks again.