SecOps Module - Radio Speech

[thegunnysgt 1]

Under the Advanced Topics section of the SecOps Wiki, it mentions that you can insert callsigns:

callsigns (leader of group, leader speech used, hq, hq speech: ["ALPHA", ["Alpha"], "H.Q.", ["HQ"]])

I noticed that when I insert my own callsigns, and SecOps comes over the radio, the callsigns are blank, I don't hear either HQ or my person saying what I have put in for them to use. I know it's because I don't have any audio that represents what I have in place, but my question is how do I?