The game definitely supports voice chat; you should be able to hear all players when entering a speedlist unless you turn them off, so the game should not be a problem.
Maybe your friends have not configured their microphone properly? That reason is most likely.
Otherwise, try to configure your speakers so that you can hear the sound of the game (but I assume that you can hear it and you can only not hear your friend).
Maybe an extremely slow internet connection is a problem?
