I think I found a way to at least minimize this issue. From the pulseaudio logs I found that for the AC3 plugin it isn't using the default fragment settings from /etc/pulse/daemon.conf which are:
default-fragments = 8 default-fragment-size-msec = 10 Instead it adjusts to the nearest latency with a default fragment size of 32 ms. So 8*10=80 ms. 32*3=96 ms is the nearest latency. It is using a default fragment size of 32 ms no matter what size I set in daemon.conf. This is what I am talking about: I: [pulseaudio] alsa-sink.c: Using 3.0 fragments of size 18432 bytes (32.00ms), buffer size is 55296 bytes (96.00ms) I: [pulseaudio] alsa-sink.c: Disabling rewind for device a52:0 I tried to lower the number of fragments and found that the frequency of the audio drops increases. It might be too frequent actually. So increasing the number of fragments should minimize the problem, right? I can increase the number of fragments to the maximum hw buffer size reported: D: [pulseaudio] alsa-util.c: Maximum hw buffer size is 320 ms D: [pulseaudio] alsa-util.c: Set buffer size first (to 3840 samples), period size second (to 480 samples). So if I set 10 or more fragments it will use 10 fragments. However when I set a too large buffer size (at leat 8 fragments) applications that play through the alsa plugin for pulseaudio will cause noise. So now I am using 5 fragments with good results so far. Here is what I have written inside daemon.conf: default-fragments = 5 # 8 default-fragment-size-msec = 32 # 10 This yields a buffer size of 160 ms. An increase of 64 ms from the original 96 ms. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1188425 Title: Audio breaks up and pulseaudio eventually crashes with Alsa a52 (ac3) plugin (Ubuntu 13.04) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1188425/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
