Comment 7 for bug 319118

Pulseaudio uses 100% CPU at the time of the freeze, and all sound applications (rhythmbox, totem, firefox with flash, etc) become unresponsive.

pulseaudio 0.9.14-0ubuntu8

alsa-util.c: snd_pcm_avail_update() returned a value that is exceptionally large: 13835058055282162564 bytes (418293516404 ms) Most likely this is a Linux bug. Please report this issue to the ALSA developers.
main.c: Called SUID root and real-time and/or high-priority scheduling was requested in the configuration. However, we lack the necessary privileges:
main.c: We are not in group 'pulse-rt', PolicyKit refuse to grant us the requested privileges and we have no increase RLIMIT_NICE/RLIMIT_RTPRIO resource limits.
main.c: For enabling real-time/high-priority scheduling please acquire the appropriate PolicyKit privileges, or become a member of 'pulse-rt', or increase the RLIMIT_NICE/RLIMIT_RTPRIO resource limits for this user.
pid.c: Stale PID file, overwriting.