That last pacmd looks good other than you weren't playing any sound at the time. I'll assume sound still isn't working.
As a test, what output do you get when you run
aplay /usr/share/sounds/alsa/Front_Center.wav
in the terminal. Was there any sound?Does
find $HOME ! -user $USER
return anything?Do you multiboot with Windows? If so, boot into Windows and test sound, then shut the computer down. Power up the computer and boot back into Mint and test again.
Hope that makes a difference.