I just upgraded from 4x WF-803M to 4x MA2500D. Using the 4x WF-803M, had no issues. Now with the 4x MA2500D, I get random drops... with no real rhyme or reason that I can tell. I did a 100 ping test several times successively... a couple of the times no issues, a couple of the times 7% and 8% loss, a couple of the times 30% and 38% loss. The adapters are directly linked in pairs: switch<--->ma2500d<--->coax<--->ma2500d<--->switch so there is no interference from anything on the coax part, especially given that the WF-803Ms worked perfectly. I see another post about disabling EEE... however, even if that IS the problem (which I'm not sure of) I can't do that on my switches. I did update to the newest firmware on the support page: v2.0.11 but it didn't seem to fix the issue... I did a couple of tests after and I was still losing packets. I need some kind of a firmware fix or a way to configure something on the adapters themselves to fix the issue.