so ...after 6 hours of cursing and swearing, I discovered this post...
I'll list all the things I tried:
-Reinstalled the game 4 times, 2 times on the same SSD and 2 times on 2 different NVME
--every uninstall I deleted the whole RS2:V folder under "C:\Users\*User*\Documents\My Games\..."
-Windows update are up to date (miracle that this didn't destroyed my PC beyond imagination)
-Updated Nvidia driver
-Port Forwarded Steam the section "Steamworks P2P Networking and Steam Voice Chat" as described here
https://support.steampowered.com/kb_article.php?ref=8571-GLVN-8711
-Port Forwarded RS2:V *the following ports ->"
https://portforward.com/rising-storm-2-vietnam/ "and these too ->" 7777 (default used by RO2) , 7779 (default used by RO2) , 27015 (used to contact the steam master server) , 8080 (default used for the RO2 web-admin)
--Restarted even my router to be sure the ports were actually applied
-white listed RS2:V on my anti virus "Avast", then joined the game
--disabled totally Avast, then joined the game
-white listed in my firewall RS2:V, then joined the game
--disabled totally windows firewall, then joined the game
-I tried every USB port in my computer with my headset
*Image "RS2Audio1"*
-I enabled and disabled every single "Playback" device
--Tried different combination with Default & Default Communication
!!_weird bug_!! that happens only with this game: once I open the game setting -> "Configure my Mic" and steam voicechat option opens, and I test my mic: after testing mic (and works) if I have set on my headset both "Default device" & "Default Communication device" the volume lowers a lot and there's no way to raise it, only way is restart the PC or set "Default Communication device" on the speakers, so the headset gains volume again.
*Image "RS2Audio4"*
-I tried swapping devices when I enabled them there, and troubleshooted when the game was opened
*Image "RS2Audio5"*
(before telling you what I did, let me point out 2 things: when you voice chat in steam what takes microphone control is "Steam Client WebHelper" and the image is not showing the game because at the moment of the screenshot I had it closed)
-I tried swapping from default to my mic/speakers from the headset, did this for: master volume, steam client webhelper, RS2V, steam
-even resetted (the button "Reset" below)
*Image "RS2Audio6"*
-I disabled and enabled the microphone multiple times for all apps
-The thing is that, as the picture shows, discord has the mic in use. When I test the mic with steam voice chat "steam client webhelper" becomes in use with the mic, but the game never got the mic in use
*Image "RS2Audio7"*
(because microsoft never stops to surprise....)
-I opened the Xbox Console Companion, and it was detecting RS2:V , once I was in game it has his own overlay; hotkey "Windows key" + G
--In the overlay I applied in every audio option my mic & headset
Nothing of the above did work, but ... let me point out what/where I believe the problem might be:
When I installed the game multiple times on different hard disks (I have 5.. don't ask why) if it wasn't where I had it first installed, the game icon under the mic permission in the *Image "RS2Audio5"* was not even showing, like the game is not even installed/recognized by windows.
At this point I thinking there's some "left over" after uninstalling that gets stuck with the first install patch for the microphone permission that doesn't get refreshed with the new path.
I really hope all this helps in any way