I'm trying out UDP communication in Unity with the Hololens. Since the .net sockets aren't available I looked at how things are done in UWP. I basically took this example: https://github.com/Microsoft/Windows-universal-samples/blob/master/Samples/DatagramSocket/cs/Scenario5_MulticastAndBroadcast.xaml.cs
The weird thing now is that I can get broadcasting to work on the device, both sending and receiving, but not multicasting. The Hololens can send multicasts that multiple laptops will receive, but when any device is sending multicast messages then they won't show up on the Hololens even though other devices will receive them.
If I run the UWP application on a laptop it does pick up the multicast messages (sent form a different laptop), so I know the messages are sent (Wireshark also shows them) and I implemented the receiving code with DatagramSocket and JoinMulticastGroup correctly. I also checked the capabilities for InternetClient, InternetClientServer and PrivateNetworkClientServer.
It's so weird that all the broadcasting stuff works on the Hololens and even sending multicast messages, just not receiving multicast message specifically on the device. What am I missing here?