Three more things to add. First, I have a very similar, slightly older laptop than this one. Same model number etc but about an 8 month earlier build with a slightly slower processor. It's a kind of "spare". It has 10.04 on it, but otherwise nothing much in the way of installed stuff. So I installed latencytop and ran it; very similar (long) latencies on it.
Second, I disconnected the USB audio card, activated the internal sound card, played some music, and a few minutes later got an underrun. So it's not related to the USB external sound card thing. Here's syslog around one of those. The shame of an underrun on Bob Marley. May 29 15:09:16 temuko pulseaudio[1261]: alsa-sink.c: Rewound 8796 bytes. May 29 15:09:16 temuko pulseaudio[1261]: sink.c: Processing rewind... May 29 15:09:16 temuko pulseaudio[1261]: sink-input.c: Have to rewind 8796 bytes on render memblockq. May 29 15:09:16 temuko pulseaudio[1261]: sink-input.c: Have to rewind 8796 bytes on implementor. May 29 15:09:16 temuko pulseaudio[1261]: source.c: Processing rewind... May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: Wakeup from ALSA! May 29 15:09:17 temuko kernel: [ 172.142568] ath5k phy0: noise floor calibration timeout (2422MHz) May 29 15:09:17 temuko pulseaudio[1261]: alsa-source.c: Wakeup from ALSA! May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: Underrun! May 29 15:09:17 temuko pulseaudio[1261]: alsa-source.c: Overrun! May 29 15:09:17 temuko pulseaudio[1261]: alsa-source.c: Increasing minimal latency to 16.00 ms May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: Increasing wakeup watermark to 50.00 ms May 29 15:09:17 temuko pulseaudio[1261]: alsa-source.c: latency set to 20.00ms May 29 15:09:17 temuko pulseaudio[1261]: alsa-source.c: hwbuf_unused=62008 May 29 15:09:17 temuko pulseaudio[1261]: alsa-source.c: setting avail_min=442 May 29 15:09:17 temuko pulseaudio[1261]: protocol-native.c: Underrun on ''Exodus' by 'Bob Marley & the Wailers'', 0 bytes in queue. May 29 15:09:17 temuko pulseaudio[1261]: protocol-native.c: Requesting rewind due to rewrite. May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: Requested to rewind 42612 bytes. May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: Limited to 5832 bytes. May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: before: 1458 May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: after: 1458 May 29 15:09:17 temuko pulseaudio[1261]: alsa-sink.c: Rewound 5832 bytes. May 29 15:09:17 temuko pulseaudio[1261]: sink.c: Processing rewind... Third, looking at the messages file, thinking of that ath5k involvement, look at the following messages. Does this indicate some fundamental problem that might be making the ath5k interfere somehow? May 23 10:03:55 temuko kernel: [ 2616.230801] WARNING: at /build/buildd/linux-2.6.32/drivers/net/wireless/ath/ath5k/base.c:1142 ath5k_tasklet_rx+0x53b/0x5 a0 [ath5k]() May 23 10:03:55 temuko kernel: [ 2616.230801] Hardware name: Satellite A70 May 23 10:03:55 temuko kernel: [ 2616.230801] invalid hw_rix: 1a -- Wireless blocks USB-Audio, leading to dropouts https://bugs.launchpad.net/bugs/579117 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
