Its actually part of the game. The voice chat changes depening on where your teammates are. If they're far away, some sound like they're robots, and the general volume drops considerably. And when iside locations like the tower, where you are surrounded by walls, you get this metallic echo. Annoying when wearing a headsett like yours. But with the standard edition headsett that came with my Xbox One, i didnt get the audio effect. But when i changed it to "Audio trough both speakers and headsett" I heard the wierd effect. But to me it just adds too the immersion off the game.