Finally decided to replace all switches with ProSafe managed switches from Netgear (GS105E-200PES / GS108E-300PES).
We constantly had client discovery problems across the network, turns out that was mostly a IGMP (Multicast protocol) problem. Now with the new 5-Port and 8-Port switches in place, we can finally enjoy live streaming from everywhere without a problem.
Also removed the last 100 MBit/s connection, so we are finally 1 GBit/s across the whole network. Replaced some areas with the new Powerline adapters from Tenda (P1002P), these support up to 1000 MBit/s :), which allows us to reduce Wifi in many areas.
Happy networking ….