When I was installing vlc on the AIO for the grandfather clock chime (Grand Father Clock Chime)
I had to make the following changes. You might need to do this too.
Change audio output to headphones/speakers:
sudo amixer -c 0 cset numid=3 <n>
(n is a number: 0=auto, 1=headphones or 2=hdmi)
Change volume on the pi by typing in a terminal (set mine to 60%):
alsamixer