Hi @Ugovic, There's a SG1024D v11 that has two little switches on the right to toggle isolation mode and loop prevention. Sadly, there was not a user manual for this specific version. From the...

@Houseofdreams_, assuming that you're using DHCP, if you can plug a computer into port 21, do you get a 10.10.10.x address?

@Antony23, all untagged members on the same vlan. The eap does have an option to set the Management VLAN. If you do that then the management VLAN id would be tagged on the eap's ports.

Hi @Antony23 The simplest setup is to make the controller and eap ports untagged members of the same vlan with the PVID set as well. The vlans mapped to the SSID need to be tagged on the eap's ports...

@dzakula, a like for like compare would be best just in case the other POE devices used to test don't have the same power requirements. Worth checking to isolate the problem to the 660s.

@dzakula, I'd still be very suspicious about two out of three going bad at the same time. Not sure how you tested the POE ports on the switch, but try plugging the bad AP into the port used by the...