Just in case you have re-mapped your keyboard I want to add this.
The game has TWO buttons for your microphone. There are two ways to talk with the in-game Voice-over-internet-protocol (VOIP).
One is "room" which you press to talk to anybody in visual range, or if you are on the ground, then the same "room" location inside an airbase while you are incorporeal (aka dead). So if you go into the O-club in an airbase (or better yet the O-club on a carrier....it has a nice view), everyone in that room will hear you if you push and talk. Nobody else will hear you, so you won't be bothering anybody all the way across the map with your chatter about having just pulled up after bombing the last fighter hangar at the base. They probably will not care. The guys at the base with you probably do care because they're in visual range with you.
FYI, if you are in the control tower, then hit your "room" mic button the keyboard to talk to your friends sitting on the runway in their planes, they can't hear you. They're in the game and their "room" is everyone in visual range (say 6 kilometers in all directions) and your "room" is the control tower. The two don't overlap.
The other button you have will transmit your microphone voice to anybody also tuned to it, which is defaulted to channel 101. So, if you have it left it alone as the default channel 101, everyone tuned to channel 101 will hear you, and range is not an issue. You can talk to anybody, which is useful if you have a team split up and out of visual sight from each other, such as a C-47 waiting in the hills for you to prepare an enemy base for takeover. This way they can talk to you and tell you to bring it in when the time is right, or just have a private chat channel to shoot the breeze and not bother anybody else with personal chatter about taxes, the news, or how your dog just chewed up your good set of dish towels for no reason. I'm sure you and your cousin think these are interesting topics to discuss, but the rest of us don't need to have the game VOIP clogged up with any of that.