I'm not here to criticize pulseaudio, but I find it immature and unnecessary. It eats system resources, causes confusions, and complicates the system by adding an extra layer without seemingly clear benefits, and I'm not the only one who thinks this way. (In fact, for more "real" complaints, refer to this link: http://amplicate.com/hate/pulseaudio )
Why does Ubuntu come with Pulseaudio as its sound server in the first place? Is there any good alternatives to this as of today?