Today I made a very strange observation: I get a download rate of about 400Mbit/s from my ISP. This rate is attainable with my MB 2016 via copper TB adapter. Today I tested the rate with my MP 5.1: I get about 200Mbit/s on ethernet port 1, however just about 90Mbit/s on the ethernet port 2. PRAM was cleared, interfaces deleted and re-generated in "SystemPreferences". Is there something known why the ethernet port 2 is slower (both links were built up with 1Gb, no corrupted packets listed)?