So, on Excelsior, there's a player character named Max, and every time he speaks (I want to say in General but could also be in other channels), other players can see his chat in the world (not just on the channel tab), no matter where they are or what missions they're in, and regardless of whether Max is on the same team/league as the other players. As if Max is an NPC in the distance whose chat bubble is visible (currently a black background with red text).
My theory is that this is so because Max is also the name of a villain of one of the missions in the Citadel Task Force, and somehow the logic is crossing over. (Or alternately, sharing a name with the contact Max.) It might not hold water after all, but thought to mention it in case it leads to something useful.