When downloading the files from the AW repository, the Userconfig files don't get copied.
There might be a better way to solve it, but I fixed it on my end by googleing Task Force Radio, downloading the most recent version (134 MBs), and then extracting the Userconfig files from that.
Simple process, easy to do, though if anyone know of a way to only get the Userconfig files and not the entire mod package, do feel free to chime in
Edit:
Just in case you need a step-by-step:
http://www.radio.task-force.ru/en/
Download the most recent version.
Locate the Userconfig folder inside it, which should house the infamous radio_settings.hpp
Copy the .hpp into your Steam\SteamApps\Common\Arma 3\Userconfig folder
Amentes's post in problem with my TFR user config was marked as the answer