[Abra Cadabra IV]

I can't seem to find anything in the rules that prevents you from doing so...but why would you want to? If it's for communication between the drive team, you're better off just talking to each other, plus you'll still need to be able to hear so you can talk to your alliance partners during the match. If it's to talk to someone in the audience...if you need to talk to someone that badly during a match, make them the coach.

Also, FIRST generally doesn't like this kind of stuff; the headsets are banned in FRC and communicating with a member of the audience (like with hand signals, etc) is worthy of a penalty there.