Aussie Airlines

Can anyone tell me how to create your own airline and have it's name used in ATC communications? Eg: "Aussie" Airlines
Flight Simulator and other chat
https://forums.simviation.com/phpBB3/
https://forums.simviation.com/phpBB3/viewtopic.php?f=30&t=87483
I tried that but i cannot get it to work in ATC [air traffic control] Communications. HOW do you get the sound files created?