On Friday 12 August 2011 12:30 AM, pulseaudio-discuss-request at lists.freedesktop.org wrote: > Send pulseaudio-discuss mailing list submissions to > pulseaudio-discuss at lists.freedesktop.org > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss > or, via email, send a message with subject or body 'help' to > pulseaudio-discuss-request at lists.freedesktop.org > > You can reach the person managing the list at > pulseaudio-discuss-owner at lists.freedesktop.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of pulseaudio-discuss digest..." > > > Today's Topics: > > 1. Re: Pops/Crackles Messing up my audio... (Nasa) > 2. Re: Need help to reduce delay with USB, mic using pulseaudio > (Pierre-Louis Bossart) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 11 Aug 2011 17:09:25 +0000 (UTC) > From: Nasa<nasa01 at comcast.net> > Subject: Re: [pulseaudio-discuss] Pops/Crackles Messing up my audio... > To: General PulseAudio Discussion > <pulseaudio-discuss at lists.freedesktop.org> > Cc: alsa-user at lists.sourceforge.net > Message-ID: > <294431320.552022.1313082565114.JavaMail.root at sz0115a.westchester.pa.mail.comcast.net> > > Content-Type: text/plain; charset=utf-8 > > > > ----- Original Message ----- > >> ----- Original Message ----- >> >>> 'Twas brillig, and Nasa at 07/08/11 21:26 did gyre and gimble: >>> >>>> Hi, >>>> >>>> I was hoping I could get some help troubleshooting some audio >>>> quality issues I am running into. >>>> Specifically, I am getting a lot of *pops/crackles* when I play >>>> audio files. It shows up when I >>>> move from 2-channel to 4/5 channel audio (via pauvcontrol) - I am >>>> using a USB X-FI sound-card with >>>> the Meego IVI. >>>> >>>> I have tried changing the resample method (going from ffmpeg to >>>> high-quality) and setting tsched=0, >>>> neither making any noticeable difference. >>>> >>>> The only things I saw in /var/log/messages that seemed relevant >>>> was: >>>> messages:Aug 6 16:59:26 localhost pulseaudio[570]: alsa-sink.c: >>>> ALSA >>>> woke us up to write new data to the device, but there was actually >>>> nothing to write! >>>> messages:Aug 6 16:59:26 localhost pulseaudio[570]: alsa-sink.c: >>>> Most >>>> likely this is a bug in the ALSA driver 'snd_usb_audio'. Please >>>> report this issue to the ALSA developers. >>>> messages:Aug 6 16:59:26 localhost pulseaudio[570]: alsa-sink.c: We >>>> were woken up with POLLOUT set -- however a subsequent >>>> snd_pcm_avail() returned 0 or another value< min_avail. >>>> >>>> And this was spout out of dmesg >>>> [ 21.857184] ALSA sound/usb/mixer.c:2110: status interrupt: c0 00 >>>> [ 21.897058] ALSA sound/usb/mixer.c:2110: status interrupt: c0 00 >>>> [ 21.961062] ALSA sound/usb/mixer.c:2110: status interrupt: c0 00 >>>> >>>> I have already eliminated the speakers and the amp (played music >>>> from a different source and >>>> they sounded fine). >>>> >>>> Let me know what else I should post (I could record the sound, if >>>> that would be useful). >>>> >>>> Thanks in advance, >>>> >>> While this could be an issue in the alsa driver itself, can I ask if >>> you're applying any volume changes to your streams or sink? >>> >>> There could be a problem with optimized paths for software volume >>> adjustments. You can disable these optimisations via a special >>> environment var: PULSE_NO_SIMD=1 >>> >> Col, >> >> So I added >> >> export PULSE_NO_SIMD=1 >> >> into my .bashrc file and rebooted. From the terminal >> "echo $PULSE_NO_SIMD" came back '1' -- however, that didn't >> make any difference in the pops/crackles I am hearing :{ >> >> Nasa >> >> >> > So, > > Is there anything else I can check, or should I place a bug report > for ALSA? > > Nasa > > > ------------------------------ > > Message: 2 > Date: Thu, 11 Aug 2011 12:48:38 -0500 > From: "Pierre-Louis Bossart"<pierre-louis.bossart at linux.intel.com> > Subject: Re: [pulseaudio-discuss] Need help to reduce delay with USB, > mic using pulseaudio > To: "'General PulseAudio Discussion'" > <pulseaudio-discuss at lists.freedesktop.org> > Message-ID:<007c01cc584e$e6bcfba0$b436f2e0$@bossart at linux.intel.com> > Content-Type: text/plain; charset="us-ascii" > > >>>> Use module-loopback and play with the latency parameters. >>>> >>> In case you don't know what the latency parameters are, on the >>> gst-launch line, you can append these parameters: e.g. >>> >>> gst-launch-0.10 pulsesrc buffer-time=<xxxx> latency-time=<xxxx> ! >>> pulsesink buffer-time=<xxxx> latency-time=<xxxx> >>> >>> >> I suspect Pierre was referring to the latency_usec param on module- >> loopback. >> > Correct. Providing data to a client and back isn't the most efficient thing > to do if you can handle this in IO threads. > > > > ------------------------------ > > _______________________________________________ > pulseaudio-discuss mailing list > pulseaudio-discuss at lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss > > > End of pulseaudio-discuss Digest, Vol 4, Issue 32 > ************************************************* > What is module-loopback? I changed buffer-time and latency-time for different values in gst-pieline but no success. It reduces delay very less amount i.e delay is still there (2-2.5 sec). When I use alsasrc and alsasink with the same usb mic getting no delay with good audio quality. Please help to solve the problem. Regards Ashwani
