It's really very strange.
I use IP address 192.0.0.x in intranet. The speed both read and write are very slow. Write speed just about 5 MB/s while read speed about 10 MB/s in ervery session. If I use other network IP like 10.1.1.100, write speed can arrive more than 40 MB/s. As I know 192.0.0.x is internet IP address. Is there any rule limit internet speed automatic? Or, is it a bug?
I test both version 6.4 and 15. All use fresh configure (Just add domain and user)