Re: no sound (not a noob)
While I have never had any problem with analog stereo sound in Ubuntu (other than default sometimes muted on fresh install) digital or HDMI audio may require additional configuration depending upon what hardware you have. In a terminal, besides trying alsamixer, see what, if any, output you get from aplay -l (small L) and aplay -L (capital L). The former should list the default audio device and latter all available audio devices. You might also post what sudo lspci -v shows about your audio device.
Note that to make things easier to follow that have indents or columns, wrap that output in code tags by highlighting it and clicking # in the message window.
I did have a problem with no sound in Lubuntu on a tablet PC. In that case alsamixer did not show any PCM device. The only way I could get it to work was to install pulseaudio and pavucontrol (but the latter is not installed in Ubuntu 12.04 and it looks like it uses indicator-sound instead). After installing pulseaudio, alsamixer showed a PCM device and sound worked.
Although, I have regular Debian sound working fine in a virtualbox using just alsa related audio.
i5 650 3.2 GHz, 8 GB, nvidia GTX 1060, 32" 1080p & assorted older computers