Hello,
I'm currently stress-testing my snd-usb-caiaq driver under several environments and happen to see a number of such messages echoed once in a while at the start of aplay (1.0.16):
underrun!!! (at least 1558380812.470 ms long) underrun!!! (at least 1558380818.673 ms long) underrun!!! (at least 1558380812.465 ms long)
Also, pulseaudio (0.9.14) keeps complaining with the following message all over the place:
E: module-alsa-sink.c: ALSA woke us up to write new data to the device, but there was actually nothing to write! Most likely this is an ALSA driver bug. Please report this issue to the PulseAudio developers.
What puzzles me a bit is that I don't really know where and how the driver could confuse the core so badly. All it reports is a valid pointer to the current head in each substream. Is there anything else it could provide for tighter syncing? Any hint how to debug this? Or maybe it's not a bug in this specific driver but in the core somewhere?
Thanks, Daniel