Open GUI -> General Configuration -> Force networking on interface -> Select your network card.
Save, stop application and start again.
But it doesn't work.
If I start PS3M when I'm connected to the internet (by ethernet), PS3M recognizes an ethernet card: "eth0 (192.168.0.10)".
But when I disconnect internet, so as to connect my computer and my Oppo BDP83 by ethernet, PS3M doen'st recognize any ethernet at all. In the networking interfaces, it just proposes "lo". But selecting that doesn't work.
Previously, I had saved the configuration with "eth0 (192.168.0.10)", but it didn't work either.