@Edwin_Aa I opened a ticket at TP-Link support. It's amazing how quickly they respond and escalated the issue. They also already did a remote session to investigate en collect traffic.

@Edwin_Aa With IPv6 disabled on the VLAN the problem is solved. Problem with IPv6 support on the EAP650-WALL.

@Virgo Thanks for your reply. Rate Limit is off, Guest Network is off and no MAC Filtering.

When setting a VLAN on the wireless the traffic is extremly slow. The clients getting the right IP of the VLAN and i can ping to e.g. 8.8.8.8 But it is almost impossible to load a webpage, e-mail ,...