my awesome WM(desktop environment) with sound problem!

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https://bbs.archlinux.org – I'm a newer to awesome .there's only one window manager awesome in my linux without any desktop environment(KDE GNOME...) or  display manager(gdm kdm...etc) ,but I encountered a problem :  there's no sound when playing music  in the awesome environment ,but it sounds  when switch to  anoter tty  on which the user of awesome DE has logined.It's really strange.... beg for help .Here's my rc.lua  about  volume:----------------------------------------------------------------------- vicious = require("vicious")volumewidget = (HowTos)