I've been trying to find the energy to stay awake when everyone else is. Adjusting to work and trying to train my body to a new sleep schedule. But that's been getting better. 
So you're having issues with people hearing you or you them in game.
Have you checked your in-game Voice chat settings? If you haven't already tried SHIFT+H to set your proximity, try that before continuing to read.
See how here - https://plays.tv/video/5a299217cbfa2539bc/voice-chat-and-population-density?from=user
If for whatever reason you checked all this and ensured you have pressed "N" if you have it on "push to talk". follow the instructions below the line.
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If still nothing, right click your volume and go to Playback devices.
Ensure only your playback device is available and all others are disabled.
The same in Recording.
Restart PC and check game settings again.
Nothing after that ? Please rebox your PC and return it to the place of purchase, you are not capable of using a PC.
Only Kidding.......... join our discord and ask for help.
Hi All,
My name is (Leon) Bendacat,
I've had no experience in Arma3
FiveM's my thing, I love the RP.
I'm here for a change, pushed by a mate but enjoying the server.
(Be good or be good at it, otherwise, you'll be pushing a pram.)