if I understand you correctly you've tried to add yourself (the user that you are on your system) to the audio-group.
If you want to check your group-membership you may execute the command "id" as this user.
For further help please provide more information about your system. Which distribution are you using. the output of the command
lspci -k | grep -iA5 audio
would be helpfull to check which sound-hardware you're using.
If you soundsystem is working, execute the command "alsamixer" on the commandline.