Hi, I got some advancement in my investigation thanks to a fine tuning on my Cisco switch.
I’ve reloaded my RPI3 with a Unbuntu server 16.04 armv7 on which I installed Roon 1.3 armv7.
192Khz not playing by default. If I activate on the Cisco switch (SL M2008) the option “Flow control” on the port connected to my router, 192Khz files are working. Great!
The “Flow control” on the LAN port connected to the RPI3 does not seem to change anything.
The JumboFrame option has no effect.
I’m still not understand why the RPI3 LAN port is viewed as a 100Mb/s as the RPI3 comes with a 1Gb/s LAN port.
The other good news is that DSD128 is now working too 
Hope this help, but this “Flow control” option is something already suggested in an another thread.
