There are many complaints that the network code got laggier during versions 1.2 - 1.3. The problem is I don't really know why it is like that. I didn't really change the network code during those versions. If you're an admin then you can change the server settings, here are my ideas:
The thing that changed most was adding PacketRate_Adjusting=1 to soldat.ini. Change it to PacketRate_Adjusting=0 on the servers and see how it plays.
You might play with the soldat.ini options for setting packet send rate T1_*, works when connection type is set to T1 (Internet_Connection=3)
example: T1_Snapshot=40, sends this packet every 40 ticks (60 ticks = 1 second). The bigger the numbers are the less bandwidth the server needs but the gameplay will not be as smooth as with small numbers.
You might also try disabling anti-cheat - Disable_AntiCheat_Kick=1.
Also you might remove all entries in lobby_servers.txt so that it doesn't communicate with the lobby servers.
Play around with these and please let me know how it works.
The thing that changed most was adding PacketRate_Adjusting=1 to soldat.ini. Change it to PacketRate_Adjusting=0 on the servers and see how it plays.
You might play with the soldat.ini options for setting packet send rate T1_*, works when connection type is set to T1 (Internet_Connection=3)
example: T1_Snapshot=40, sends this packet every 40 ticks (60 ticks = 1 second). The bigger the numbers are the less bandwidth the server needs but the gameplay will not be as smooth as with small numbers.
You might also try disabling anti-cheat - Disable_AntiCheat_Kick=1.
Also you might remove all entries in lobby_servers.txt so that it doesn't communicate with the lobby servers.
Play around with these and please let me know how it works.