Xorg (pulseaudio) temporarily freezes with 100% CPU on startup

[Rocko]

Binary package hint: pulseaudio

During startup in Hardy (kernel 2.6.24-21-generic) and Intrepid (2.6.27-7-generic), X temporarily freezes at a random point for up to 20 seconds. If I ssh in from another machine, I can see xorg is using 100% CPU.

It is random because it happens sometimes before, sometimes after, and sometimes even during when the gnome-panel is being drawn.

When it freezes, the spinning cursor stops spinning, although moving the mouse still moves the cursor.

Version information (for Intrepid):

kernel 2.6.27-7-generic
xorg version 1:7.4~5ubuntu3
pulseaudio 0.9.10-2ubuntu10~ppa1

Attached is the output of lspci and lsusb.

The syslog timestamps indicate it might be a problem with pulseaudio, as each message is reported in rapid sequence until pulseaudio starts reporting errors. For example:

Oct 31 09:45:25 galactica pulseaudio[6777]: ltdl-bind-now.c: Failed to find original dlopen loader.
Oct 31 09:45:25 galactica pulseaudio[6780]: main.c: setrlimit(RLIMIT_NICE, (31, 31)) failed: Operation not permitted
Oct 31 09:45:25 galactica pulseaudio[6780]: main.c: setrlimit(RLIMIT_RTPRIO, (9, 9)) failed: Operation not permitted
Oct 31 09:45:39 galactica x-session-manager[6711]: WARNING: Application 'gnome-wm.desktop' failed to register before timeout
Oct 31 09:45:49 galactica x-session-manager[6711]: WARNING: Application 'libcanberra-login-sound.desktop' failed to register before timeout
Oct 31 09:45:49 galactica x-session-manager[6711]: WARNING: Could not launch application 'Screenlets%20Daemon.desktop': Unable to start application: Failed to execute child process "/usr/share/screenlets-manager/screenlets-daemon.py" (No such file or directory)
Oct 31 09:45:53 galactica kernel: [ 78.432074] CE: hpet increasing min_delta_ns to 15000 nsec
Oct 31 09:45:54 galactica kernel: [ 79.016072] CE: hpet increasing min_delta_ns to 22500 nsec
Oct 31 09:45:54 galactica kernel: [ 79.600072] CE: hpet increasing min_delta_ns to 33750 nsec
Oct 31 09:46:12 galactica pulseaudio[6780]: module-x11-xsmp.c: X11 session manager not running.
Oct 31 09:46:12 galactica pulseaudio[6780]: module.c: Failed to load module "module-x11-xsmp" (argument: ""): initialization failed.

Sound and microphone both work (although there are some important bugs in Intrepid - eg the microphone digital sensitivity control is not available in Intrepid although it is in Hardy), so this is different from eg bug #286430.