For a while now we have been considering some of our options of improving this. I have also discussed it with you before Winkler
As some of you may know, our voice chat is based on TeamSpeak. After having been in communication with TeamSpeak support for a bit, they suggested we set a whisper list for each player on the server, which means that for each game frame, the server has to calculate and create a list for each player containing which other players this player is close to. Then when a player starts speaking, the voice data will only be transmitted to the players on his list who are close to him. We already have the lists for each player calculated and generated in an efficient way, however setting the list on each player on the TeamSpeak server havent seemed to have any effect, the server still sends data to you even if you are not on their whisper list.
The functionality is the same mostly as when you set up whisper lists on the regular TeamSpeak client. The only difference is that when you do it on the teamspeak client, your client sends a request to the server, to add a player or a channel to your whisper list. We would like to avoid this however as when players move around in the ingame world, all clients would constantly be sending requests to the server over the network to remove and add players. The TeamSpeak SDK also supports setting the whisper list directly on the server, from what I can tell, this is however some functionality that isnt used very often so it is possible there are some issues with this feature in the current version of TeamSpeak. We'll see what they tell us when their support gets back to us.
There is of course no guarantee that this will fix any of the issues. But in a game like War of Rights on a full server. You of course never notice it to its full extent, but in a melee charge, it is possible that 50 or more players are speaking in the voice chat at the same time, which then makes the TeamSpeak server send 50 audio streams to all players at the same time which I would imagine would be a fair amount network data.
This has been a known issue for a long time now, it is mostly related to some USB and Bluetooth headsets behaving like this. There is currently no fix available other than to use a different headset. However with the stuff I was talking about above. When we get the whisper list on the server to work properly, hopefully within the next week. This would make the server only send voice data to you from players who are within the normal voice chat volume falloff distance which is 35 meters. You will then still only hear players speaking at full volume, but it will only come from those players close to you.