Description of problem:
Skype audio was cutting in and out for unknown reasons.  I opened the volume control mixer to adjust my microphone volume to see if that would affect it.  This happened.

Version-Release number of selected component:
pulseaudio-2.1-6.fc18

Additional info:
backtrace_rating: 4
cmdline:        /usr/bin/pulseaudio --start
crash_function: pa_alsa_path_set_volume
executable:     /usr/bin/pulseaudio
kernel:         3.8.1-201.fc18.x86_64
uid:            1000

Truncated backtrace:
Thread no. 1 (10 frames)
 #2 pa_alsa_path_set_volume at modules/alsa/alsa-mixer.c:1053
 #3 source_set_volume_cb at modules/alsa/alsa-source.c:1196
 #4 pa_source_process_msg at pulsecore/source.c:2007
 #5 source_process_msg at modules/alsa/alsa-source.c:1083
 #6 set_shared_volume_within_thread at pulsecore/source.c:1921
 #7 pa_source_process_msg at pulsecore/source.c:1999
 #8 source_process_msg at modules/alsa/alsa-source.c:1083
 #9 asyncmsgq_read_work at pulsecore/rtpoll.c:564
 #10 pa_rtpoll_run at pulsecore/rtpoll.c:238
 #11 thread_func at modules/alsa/alsa-source.c:1514