Players are reporting hearing Military Chatter while driving around as Trevor. This may occur, because of Trevor being in Canadian Air Force in the past.
The CB Radio signals can only be heard when Trevor is in his Bodhi or any other car with a CB Radio installed in it, such as a Dune Buggy.
The chatter is a very rare occurrence, but with patience is still possible to hear.
Trevor will only respond to the chatter in a few situations.