If you use this app on Android, like I do, you might be interested to know you can rip the audio from the game very easily. The audio is stored on the sdcard which you can access using ADB or plugging your device into your computer and browsing to
In this folder are two files:
One contains the main audio, the other contains the additional missions (Supply Runs, etc.) and the radio audio clips. Extract them both to a folder (they’re ZIP files, even though they have a .obb extension), and you’ll get MP3 audio files.