It is a known issue in Ubuntu that the when a HDMI cable is plugged in, the sound settings do not automatically show the HDMI sound output option. The only way to make it work was to log out and log back in again with the HDMI cable plugged in. This bug is discussed here: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/974963 But the page also lists a very useful workaround thanks to Beltrachi, The idea is to send noise to the hdmi output. $ cat /dev/urandom | aplay -f S16_LE -c2 -r44100 -D hdmi Press Ctrl+c when the noise is heard in the TV. The hdmi should be working now. The sound in the speaker might disappear after the hdmi cable is unplugged. The dosage is similar for this case also. Just send noise to the default speakers. $ cat /dev/urandom | aplay -f S16_LE -c2 -r44100 If that doesn't seem to work then try to select the PC speakers as the output device in the Sound controls.