solved it using $ ubuntu-bug audio
it appears that "speaker volume" was set to 0%, which is hidden in Sound Preferences => 1. $ alsamixer -c1 1b. if not installed => $ sudo apt-get install alsamixer 2. pull sound volume up
solved it using
$ ubuntu-bug audio
it appears that "speaker volume" was set to 0%, which is hidden in Sound Preferences
=>
1.
$ alsamixer -c1
1b. if not installed =>
$ sudo apt-get install alsamixer
2. pull sound volume up