To achieve native support for MUMBLE's LINK there is need to add small code blocks into Arma 3 source :
http://mumble.sourceforge.net/Link
(init code block plus there is portion for updating player position in meters inside 3D world each frame - for positional audio)
additionally these code portions may be inert until activated by setting entry:
e.g. in Arma3.CFG and Arma3server.CFG (MumbleLink=0/1; where 1 true).
Important:
Mumble Link is public domain open-source & documented, it can be utilized by even plugin written for e.g. TeamSpeak 3
Note:
Voice communication tools like ACRE can utilize this to improve theirs functionality
In nutshell: the Mumble's LINK is universal information export interface ... which can be used even by TS3's plugins ... like ACRE ...