If you’re having audio trouble in a recent build of Ubuntu, ESD just might be the cure for you. It’s an older technology, but for me (ALC887 sound card on Ubuntu 10.04), it fixed my sound crackling issues while using PulseAudio and ALSA. It’s easy to try!
Type into your console:
sudo apt-get install esd gstreamer0.10-esd gstreamer-properties
Make sure to stop all current sound from playing, then select ESD as the default audio output. Hit the “Test” button to verify that ESD works.
It might not help, but it’s not advice I’ve seen around the internet, and it solved my problems