While running an amateur radio application on a Raspberry Pi 3B+ with the stretch version of Raspberrian, I see the following in my syslog:
Aug 1 17:31:06 raspberrypi pulseaudio[853]: [alsa-sink-USB Audio] alsa-sink.c: ALSA woke us up to write new data to the device, but there was actually nothing to write. Aug 1 17:31:06 raspberrypi pulseaudio[853]: [alsa-sink-USB Audio] alsa-sink.c: Most likely this is a bug in the ALSA driver 'snd_usb_audio'. Please report this issue to the ALSA developers. Aug 1 17:31:06 raspberrypi pulseaudio[853]: [alsa-sink-USB Audio] alsa-sink.c: We were woken up with POLLOUT set -- however a subsequent snd_pcm_avail() returned 0 or another value < min_avail.
So...I am reporting this to the developers as instructed by the error message. What additional information do you need?
I'm not exactly sure what I was doing to trigger this error. I may have been exiting the application.
Thanks, Harry Bloomberg