VLC UDP Stream - reception not possible on other devices in the network

[FrazeColder1]

Hello, everybody,

I have installed the VLC Player on my MacBook Pro and would like to use it to stream videos to my local network. Therefore I go to File -> Conversion/Stream in VLC, select the file and set the streaming setting to UDP, the address to 192.168.178.23 and the port to 18000 (That's why the lower ports are "protected" in MacBook).

IP address MacBook: 192.168.178.23.
IP address iPhone: 192.168.178.26.

If I open a second instance of the VLC player on the MacBook itself and enter udp://192.168.178.23:18000, I get picture and sound without any problems.

However, if I want to receive the stream on my iPhone and I enter the IP address of the iPhone in the VLC app on the MacBook, i.e. 192.168.178.26 and the port 18000, and on my iPhone I enter the IP address of the MacBook, i.e. udp://192.168.178.23:18000, then the app unfortunately shows me nothing but a black screen. Unfortunately I don't know why.

On my MacBook the firewall is disabled. I have installed a program called Network Monitor, which can prevent network connections, but VLC is released. It doesn't make any difference if I turn this program off. I just don't get sound and picture on other devices... So I can't explain which program or firewall is blocking this connection.

If I look at the whole thing with Wireshark, Wireshark says that the video is streamed from MacBook (192.168.178.23) to iPhone (192.168.178.26). However, Wireshark also says that the request from the iPhone to the laptop is not possible. The answer is: "Destination unreachable (Port unreachable)".

Could you help me somehow and tell me why?
Unfortunately, it makes no difference whether I use port 18000 or 8080...

Many thanks