What is the difference between the TL-PA8030P and the TL-WPA8630P from a technical perspective besides the WLAN of course?
Why does the version without WLAN work with Telekom Entertain TV and my version with WLAN not?

TL-PA8030P, with firmware from March 2016 at least, handles multicast correctly on the powerline and integrated LAN switch.

Multicast on WLAN is much more difficult, and a recent test in Germany found that few adapters actually do get it right. AVM and Devolo passed, everyone else did not do quite so well.

But even if I turn the WLAN off it dies not work.Also to create no misunderstanding: the Mediareceiver needed to watch EntertainTV (12 MBit needed only) had to be connected via LAN. I do not even need the WLAN of the Powerline Adapter.Is this an official answer that THIS Adapter is not capable to do. the job? WHO does the other one work them?

The point is, if any one of the infrastructure devices does not understand multicast traffic, then this device will flood your local network with broadcast traffic. So even if you connect your EntertainTV box via LAN, a non-multicast aware WLAN AP in its path will start firing the media stream to everything that is connected through WLAN as well. Same goes for simple LAN switches. They have to be multicast-aware or else Entertain will fail in ways you wouldn't even think of.

Also, from my own experience, connecting the Entertain box via Powerline does work OK as long as you have just one Entertain box. If you add secondary receivers elsewhere in the house, you absolutely need to have the primary one on a direct LAN connection to the router.

Thanks Peter for the detailed answer.
However, I do not see that any of this applies in my setup.

I use a T-Link VR900v as DSL Modem with 100MBit connection. Location 3 meters (but 1 door why I do not want to make a hole into he wall for the LAN cable) from the Entertain TV box. Connection works w/out problems. No bad traffic from a WLAN as you described. I lack the technical understanding of what you write but just as a matter of fact, this does not happen. WLAN is not “firing” the media stream blocking the connection. Otherwise it wouldn’t work with LAN, right?

I only use a TP-Link Archer and the Powerline Adapter. No other stuff around. No 2nd Media Receiver. Etc.

But if I connect the Entertain box via Powerline, even with deactivated WLAN of the TL-WPA8630P btw. it won't work.
I can't imagine why the WLAN of the Archer should interfere here. It’s a LAN and Powerline connection.

Again: it works VERY GOOD with the DEVOLO product… according to the telekom forum it also works with the TP-Link TL-PA8030P (same model w/put WLAN). So???

--> I’d expect a TP-Link technichian to reply to this problem or at least inform that this is being looked at.

Otherwise I have to sell my TP-Link powerline adapter - and fore sure not buy one again but from Devolo + will replace the Archer as soon as possible with soemthing else.
Support is a very important argument when buying a technical product.

Hope TP-Link qualifies to be a real alternative here, too.

My personal experience with Entertain (the original) is that it's ridiculously fragile. While streaming is quite stable, communication between Entertain servers and the receiver, as well as communication between multiple Entertain receivers, frequently drops out of sync whenever the slightest little disturbance is in your network.

EntertainTV (the new stuff) seems to be even worse. Forums are full of people wrestling all kinds of weird errors, good success patterns only from those people with direct LAN connections and known-good routers from either Telekom themselves or AVM.

That said, I am very glad that my ISP did not switch from Entertain to Entertain-TV, so I get to keep my 1st-generation receivers that work stably even in my rather complex home network.

Ok thanks for the opinion on Entertain and Entertain TV but that has nothing to do with my problem. ;)

We are not talking about bad quality, disruptions, synch problems etc. It works PERFECT with LAN and works NEVER after 5 seconds with the Powerline --> no discussion needed that THIS is the problem!
All you say is not adressing to my real question if there are and known problems with the IGMP protocol?

WHO from TP Link will ever look at this and post and answer?? Is this a user help users forum or an official forum of TP Link? Where is the support?
:( :(

Thing is, Entertain initially uses single-cast traffic even for the video stream, and switches to multicast after a few seconds - and that's when you see it fail. I have no doubts that this is due to a multicast-unaware component somewhere in your setup.

It's just that I'm not sure you have just one such component - the 8630P may not have IGMP snoop and multi-to-unicast conversion towards the WLAN, _and_ your router may or may not handle multicast traffic correctly either.

What I was saying above is that even once everything you have is fully multicast aware and has plenty of bandwidth, the Entertain solution still remains unbelievably fragile.

https://telekomhilft.telekom.de/t5/Fernsehen/EntertainTV-neu-Liste-funktionierender-Kombinationen-mit-WLAN/m-p/1867188/highlight/true#M133989

Thanks Peter! I think I understand now what you mean.

I was just in contact with the helpline and received a Beta Firmware which I will now test.
Maybe that helps.

Ok, the Beta-Firmware did NOT solve the problem. Besides that the version is dated 18.4.2016 while the official version of the firmware is 6.6.2016 (??) I updated, rebooted, tried with or without WLAN on. I changed receiver and sender unit. Nothing helped.As I only have the VR900v and the Media Receiver 400 with LAN connected wehen it works and the powerline between this wenn it does not work AND as it worked with the Devolo device, I am 100% sure that the Powerline itself is the problem.