UDP Multicast not receiving any packets

[Ing-Dom]

Hi,

I have a ESP32 Hardware (WROVER-E) with a LAN8720 Ethernet Phy.

I want to send and receive data over udp multicast - and i just use the WifiUdp class for that purpose.

I get it running with a basic programm and the multicast packets are comming in fine.


The real use case is a different one, I want to extend an existing project with a protocoll using multicast.

But in that firmware, I just don't receive the udp multicast packets after beginMulticast()
I can perfectly receive packets when I use begin().. so in general, Ethernet and TCP-IP are working fine.
Also the hardware seems to be working fine.

So somewhat in the fw seems to prevent me from receiving that packages, but I have NO idea to track that down where and why these packages get lost in the TCP/IP stack.

Its a plattform io project using the latest arduino framework for esp32..

For reference
https://github.com/Ing-Dom/EMS-ESP32/bl ... rm.cpp#L53