I have found what problem cause the realplayer refuse to play sound, as I think when esd is running on background, so there will conflict with realplayer, and also with vmware server, both of them say "there is another application using the device".
-- gstreamer0.10-fluendo-mp3 conflicts with RealPlayer 10 https://launchpad.net/bugs/49242 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs