Broken pipe: Underrun occurred.

Help
2007-08-20
2013-06-03
  • Adam Spiers
    Adam Spiers
    2007-08-20

    Hi,

    With CLI and GTK interfaces to 0.3.5 and 0.3.6 I'm getting choppy audio - it's dropping audio and video frames regularly (although A/V stays in sync):

    Initial recording window is set to:
    X:0   Y:0    Width:1440    Height:900
    Adjusted recording window is set to:
    X:0   Y:2    Width:1440    Height:896
    Your window manager appears to be Openbox

    Initializing...
    Buffer size adjusted to 4096 from 4096 frames.
    Opened PCM device hw:0,0
    Playback frequency 22050Hz is not available...
    Using 44100Hz instead.
    Recording on device hw:0,0 is set to:
    2 channels at 44100Hz
    Capturing!
    Broken pipe: Underrun occurred.
    Broken pipe: Underrun occurred.
    Broken pipe: Underrun occurred.
    Broken pipe: Underrun occurred.
    Broken pipe: Underrun occurred.
    Broken pipe: Underrun occurred.
    Broken pipe: Underrun occurred.
    Broken pipe: Underrun occurred.
    Saved 44 frames in a total of 48 requests
    Shutting down.....
    Encoding started!
    This may take several minutes.
    Pressing Ctrl-C will cancel the procedure (resuming will not be possible, but
    any portion of the video, which is already encoded won't be deleted).
    Please wait...
    [97%] v
    Encoding finished!
    Wait a moment please...

    Done.
    Written 811627 bytes
    (661952 of which were video data and 149675 audio data)

    Cleanning up cache...
    Done!!!
    Goodbye!

     
    • Adam Spiers
      Adam Spiers
      2007-08-20

      I should have mentioned that this is on a 2.33GHz Intel Core 2 Duo T7600 (Dell Latitude D620) with 2GB RAM and nothing else running.  CPU remains reasonably low while the recording runs.  I have tried recording the whole 1440x900 desktop and a much smaller xterm, but the latter is just as bad.  Also tried with and without on-the-fly encoding.

      If I use --no-sound, the underruns completely vanish, but of course that makes the program useless to me.  Distribution is SUSE Linux Enterprise Desktop 10 SP1 with Intel HDA driver:

      /lib/modules/2.6.16.46-0.12-smp/kernel/sound/pci/hda/snd-hda-intel.ko

       
    • Adam Spiers
      Adam Spiers
      2007-08-20

      I finally figured it out - needed to add position_fix=1 to the options of the snd-hda-intel kernel module driver in /etc/modprobe.d.