Hey guys, I got this sound issue on archlinux.I have this problem for a long time and I really dont know why.
I will display my situation really carefully：
1：I have installed alsa-utils.
2: I can invoke alsamixer under tty(any user).
3: root can invoke alsamixer under a desktop environment and this super user can play sound without any pressure.
4: a normal user, however, can invoke alsamixer under tty but not under a DE, no sound output either.
the output is :
In addition:
I have tried several desktop, wm, such as kde xfce and awesome. I got same result.
some guys say that I need to add user to audio group, but it didnt work. As arch wiki says, local user needn't added into audio group.

Can anybody help me on this? Really apreciate for your help

Are you a member of the 'audio' group ? Sounds like a permission issue.

I hope it is a permission problem, I just added myusr in audio group by
Do I need to do reboot or do something else?
Appreciate your help.

I don't believe so but it couldn't hurt.

Groups are provided at login. So changes to the groups of a logged in user don't take immediate effect. Also no need for reboot, just logout and back in again.