You most likely didn't add your user to the recommended groups, which would give you access to the audio devices under runlevel 4 (runlevel 3 will automatically assign users to groups, but it doesn't happen in runlevel 4). If you used the
adduser script to create your user, you're prompted to add your user to additional groups by pressing the up arrow. To add your user to the recommended groups, run the following command as root, replacing $USER with your username on the computer.
Code:
usermod -a -G lp,floppy,audio,video,cdrom,plugdev,power,netdev,scanner $USER