Voice chat's speaker and muted speaker are Lucide's volume-2 and volume-x (1.53.0, ISC: port/assets/icons/lucide, credited in AUTHORS.md, its licence shipped beside the game), drawn white into the menus' bitmap voice/speaker by tools/ce_menus.py and tinted, in place of the speaker made of rectangles. In the lobby, on the scoreboard and in the list of who talks, the icon is centred on the middle of the text's capitals (draw_unicode_string_capital_middle).