Comment 2 for bug 651785

That bug doesn't contain more specific information that is needed to try and work out your problem. Please run this command in a terminal: apport-collect -p alsa-base 651785 so we can get the needed information from the machine. Please also follow the instructions here, https://wiki.ubuntu.com/PulseAudio/Log so we can get a better idea of what may be going on with pulseaudio when the crackling occurs.

 affects ubuntu/pulseaudio
 status incomplete