Comment 78 for bug 479296

I've been able to prevent this issue from happening, by disabling Pulseaudio (as per the excellent guide at http://www.jeffsplace.net/node/12 )

I should probably clarify that this initially started happening to me with Karmic, but continued to occur after having upgraded to Lucid. My system (Intel D945GCLF2, Atom 330, running Lucid w/ 2.6.32-24-generic) has had no problems at all except when I'd recently been running some audio or video-with-audio; then I'd randomly fall into a situation desribed above where the screen and mouse would freeze / lock up (but I could still ssh in to it and restart it etc.) . But, again, now that Pulseaudio is out of the picture, I've not had a single lock up.