Tendo problemas com softwares de abertura do terminal (incluindo wireshark e gedit)

Question

Estou usando o Ubuntu 14.10 e estou tendo erros ao abrir softwares do terminal. Por exemplo:

build@build:/usr/local/bin$ sudo wireshark
gdk_mir_display_open
Failed to connect to Mir: Failed to connect to server socket: No such file or directory

(wireshark:4309): Gtk-WARNING **: cannot open display: 

e

build@build:~$ sudo gedit &
[1] 4321
build@build:~$ gdk_mir_display_open
Failed to connect to Mir: Failed to connect to server socket: No such file or directory

(gedit:4322): Gtk-WARNING **: cannot open display: 

Não consegui encontrar nenhuma solução para esse tipo de erro na internet. Por favor ajude!