Comment 3 for bug 996906

>
> ( 684.030| 5.000) I: [alsa-sink] alsa-sink.c: Underrun!
> ( 684.030| 0.000) I: [alsa-sink] alsa-sink.c: Increasing minimal latency to
> 26.00 ms
> ( 684.030| 0.000) D: [alsa-sink] alsa-sink.c: Latency set to 26.00ms

The latency is too small, it will make pulseaudio more busy and could not read enough data. So would you have a try to tune the default buffer size and check what will happen?

for me i once met similar case, flood of underrun message caused by too little buffer size, it become better by tune "default-fragment-size-msec" at:
/etc/pulse/daemon.conf

>
> ...and it goes on.
>
> The "Underrun!" messages alone happened a few times before, but it didn't skip.
>
> I'd like to use PulseAudio, but it's pretty annoying having audio skip all the
> time.