Mytek Brooklyn Bridge II another great streamer too. But……
As for the LUMIN is has Leedh Processing Volume control. Meaning the streamer works as a pre amp (exceptionally well). Mytek does this too ( no pre needed) but not with Leedh. Worth a read on Leedh!
There’s gobs of info on these forums about cleaning up your Ethernet connection. Some have reported great or little success with an EtherREGEN. I’m in the plus column big time and I can’t stress enough that upgraded linear power, and cables play a big roll.
Could you run optical/fiber (cheap too) to your new setup?