sample: sockets\udp_multicast, idf4.3.2
connections: use esp32s2(with w5000) to connect other devices via pc2pc cable

Here are the test results:

1. esp32s2 connects to a host of python simulator running on Raspberry Pi
   a) if esp32s2 listens on "ff02::1:ffxx:xxxx" and sends multi cast udp to "ff02::1", esp32s2 successfully receives udp response from simulator.
   b) if esp32s2 listens on "ff02::1" and sends multi cast udp to "ff02::1", esp32s2 can not receive udp response from simulator.

2. a client of python simulator running on Raspberry Pi connects to a host of python simulator running on Raspberry Pi
   a) if client listens on "ff02::1" and sends multi cast udp to "ff02::1", client successfully receives udp response from simulator.

3. a client of python simulator running on Raspberry Pi connects to smart meter device of third party.
   a) if client listens on "ff02::1" and sends multi cast udp to "ff02::1", client successfully receives udp response from simulator.

4. esp32s2 connects to smart meter device of third party.
   a) if esp32s2 listens on "ff02::1:ffxx:xxxx" and sends multi cast udp to "ff02::1", esp32s2 can not receive udp response from smart meter device of third party.

Could you please check why scenario of 1.b, 4.a failed?
Thanks for your help in advanced, it is really urgent for us.