The sound on a desktop PC running Debian Jessie has stopped working - no
sound from any websites (e.g. BBC or YouTube) and trying to play a standard sound file I have saved which is
used to test the sound with vlc gives:
Audio output failed:
The audio device “default” could not be used:
Device or resource busy.
and in the terminal window it says:
VLC media player 2.2.6 Umbrella (revision 2.2.6-0-g1aae78981c)
[00000000013f0608] pulse audio output error: PulseAudio server connection failure: Connection refused
 core libvlc: Running vlc with the default interface. Use ‘cvlc’ to use vlc without interface.
[00000000013f0608] alsa audio output error: cannot open ALSA device “default”: Device or resource busy
[00000000013f0608] core audio output error: module not functional
[00007fc2a8c02b08] core decoder error: failed to create audio output