@Gerbenf1 

So it looks like its working for me.

Not sure if the last firmware is involved with the solution.

 

My setup:

OC200

ER605

TL-SG2008P

 

Settings:

 

Under Wired Network -> Internet -> Advance settings:

 

Under Wired Network -> LAN

Create a new LAN

 

I named it KPN-IPTV

 

VLAN: lets say 40, it must not be 4 (we need that later)

IGMP Snooping: ON

DHCP Server: ON

 

Advanced DHCP Options

Option 60: IPTV_RG

 

Switch:

We need to configure two ports with the profile of KPN-IPTV.

1 for the KPN TV box and 1 for the extra WAN port that we configure later on.

 

Under Wired Network -> LAN choose Switch Settings.

Click on the Swich and edit the port to the needed profile:

 

Enable IPTV service under Services -> IPTV:

My settings:

 

 

If you enable this service and select a WAN/LAN port, the connection with your isp will go down for about 5 mins.

 

In my case I had some problems when using WAN/LAN2.

The connections didn't come back.

So I uses WAN/LAN3 instead.

 

The last step what did the trick for me, was to connect the configured switch port for KPN-IPTV to the WAN/LAN3 Port.

And ofcourse the other configured port to the TV box.

 

Hope this helps.