How can I get my publicist to stuff it?

According to this thread, if you want to remove the voices, you need to find the file 'en_generic.nfs' in the audio speech folder and delete or rename it.

According to some people, this kills all voice audio in the game, including the co-driver voice, so you might not want to take this option if you want that voice to remain in game. Others have claimed that it doesn't remove the co-driver voice, though, so it is really a gamble.

I just accidentally discovered, that if I switch the game (on pc) from full screen to windowed, it cancels whatever voice is talking. THen I can switch back and continue playing. Weird, but it works.