Stealth Boombox
Guard gadget. Once placed, player can swap to it like bloon cam. Boombox has forward facing camera+area mic and two functions: left click plays loud sound - so if you spot someone you can let your team know there's someone near the boombox (+new options for audio customisation); right click projects your mic input through the speakers, so you can feed false info/taunt righteously/MC over some phat beatz. Can be turned off by others. If shot, goes boom.
Idea for sounds it can play - short musical loops with siren/alarm sounds. Example, boombap beat with a police siren over it.