Comment 12 for bug 330006

PulseAudio cannot currently switch between glitch-free (and not) without an explicit (manual) default.pa reconfiguration and restart. Your configuration (and mine) seems amenable to glitch-free usage, but a great many other jaunty users have configurations that are not. Until the most severe of the bugs in the audio stack are worked out, there is no one global setting that will work well for everyone.