# Audio woes **URL:** \ **Category:** GNU Radio\ **Created:** [August 8, 2015, 10:34pm UTC](https://www.ruby-forum.com/t/audio-woes/242940 "2015-08-08T22:34:30Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Rafa\_F](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/958977/32.png) [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Post date:** [August 8, 2015, 10:34pm UTC](https://www.ruby-forum.com/t/audio-woes/242940/1 "2015-08-08T22:34:30Z")
I have a Xeon server system with a SB X-Fi USB sound module on it. Changed configuration so that system sounds play on it, etc. Youtube works just fine. But any GR app that tries to use it gets _massive_ underruns, regardless of the sample rate I use–I’ve tried 48K, 32K, 8K, 44.1K, 96K. The pulse audio daemon appears to be configured for 44.1K as its natural rate. And as I said, system sounds and Firefox have no problem with audio output at all. This is F20. What do I need to know? [As an aside, I hate Linux audio. It’s the most fragmented and frustrating piece of Linux, and I’m a total Linux fanboy, but I hate sound configuration, and the “brand-new sound architecture of the week”]. ---
**Author:** ![Marcus\_DSLeech](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/74df32/32.png) [@Marcus\_DSLeech](https://www.ruby-forum.com/u/Marcus_DSLeech)\ **Post date:** [August 8, 2015, 11:21pm UTC](https://www.ruby-forum.com/t/audio-woes/242940/2 "2015-08-08T23:21:49Z")
Hi Marcus, I do agree on the “Linux audio is fragmented, and neither PA nor ALSA are consistent in documentation and configuration, and that’s seriously irritating” aspect. So, first of all, I always try to circumvent Pulse. Try sysdefault as audio device name (that’s the physical device that pulse uses, on FC21/22; I think it was on FC20, already). `aplay -L` might tell you things I can’t 😉 Other than that: might be systematic[1]. Did I mention I /really like[2]/ how Ubuntu doesn’t try to bring people to discuss problems with the upstream developers? Best regards, Marcus [1] [Bug #1051665 “[USB-Audio - SB X-Fi Surround 5.1 Pro, playback] U...” : Bugs : alsa-driver package : Ubuntu](https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1051665) [2] very much, it makes my head hurt, how much I like Ubuntu. ---
**Author:** ![Marcus\_DSLeech](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/74df32/32.png) [@Marcus\_DSLeech](https://www.ruby-forum.com/u/Marcus_DSLeech)\ **Post date:** [August 8, 2015, 11:27pm UTC](https://www.ruby-forum.com/t/audio-woes/242940/3 "2015-08-08T23:27:40Z")
On 08/08/2015 05:20 PM, Marcus M. wrote: > Hi Marcus, > > I do agree on the “Linux audio is fragmented, and neither PA nor ALSA > are consistent in documentation and configuration, and that’s > seriously irritating” aspect. > > So, first of all, I always try to circumvent Pulse. Try sysdefault as > audio device name (that’s the physical device that pulse uses, on > FC21/22; I think it was on FC20, already). `aplay -L` might tell you > things I can’t 😉 > Yeah, tried sysdefault, tried playing with what aplay -L told me. All > the same. Massive Ua underruns and sound that isn’t even close to > resembling what > I’m trying to do. It’s frustrating because both system sounds and Firefox sound are working perfectly fine. ---
**Author:** ![Marcus\_DSLeech](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/74df32/32.png) [@Marcus\_DSLeech](https://www.ruby-forum.com/u/Marcus_DSLeech)\ **Post date:** [August 9, 2015, 10:28pm UTC](https://www.ruby-forum.com/t/audio-woes/242940/4 "2015-08-09T22:28:44Z")
On 08/08/2015 10:15 PM, Marcus D. Leech wrote: > > > FC21/22; I think it was on FC20, already). `aplay -L` might tell you > > > Things got a bit better when I did a: > > > Traceback (most recent call last): > > > RuntimeError: audio\_alsa\_sink > > > timing and > > > perhaps ASLR, you occasionally “sneak through”, and don’t provoke an > > > “Invalid Argument” error way down deep in audio\_alsa. > > Sometimes with my larger flow-graph, I’d make a random change to it, > like changing the taps on a filter a bit, and that would cause it to > start working > again slightly more frequently. Sure smells like a memory > stomper… ☹ ☹ More information. On my laptop, running exactly the same F20 load, with all the same updates applied, same version of UHD, Gnu Radio, and friends, the audio sink comes up every time, whether I’m using the on-board audio hardware, or any of my USB audio dongles. So now, I don’t know what to think. My lappy is an i5, the “troublesome” system is a Xeon E3. ---
**Author:** ![Marcus\_DSLeech](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/74df32/32.png) [@Marcus\_DSLeech](https://www.ruby-forum.com/u/Marcus_DSLeech)\ **Post date:** [August 9, 2015, 4:16am UTC](https://www.ruby-forum.com/t/audio-woes/242940/5 "2015-08-09T04:16:15Z")
On 08/08/2015 05:26 PM, Marcus D. Leech wrote: > > things I can’t 😉 > > Yeah, tried sysdefault, tried playing with what aplay -L told me. All > > the same. Massive Ua underruns and sound that isn’t even close to > > resembling what > > I’m trying to do. > > It’s frustrating because both system sounds and Firefox sound are > working perfectly fine. > Some follow-up. Things got a bit better when I did a: sudo yum -y install alsa-\* In that I could now use hw:X,Y specs and some of the time, it would work, but a _lot_ of the time it would raise an exception: Using Volk machine: avx\_64\_mmx\_orc INFO: Audio sink arch: alsa ERROR: [hw:0,0]: snd\_pcm\_sw\_params: Invalid argument Traceback (most recent call last): File “./multi\_chan\_pulsar.py”, line 471, in tb.start() File “/usr/local/lib64/python2.7/site-packages/gnuradio/gr/top\_block.py”, line 109, in start top\_block\_start\_unlocked(self.\_impl, max\_noutput\_items) File “/usr/local/lib64/python2.7/site-packages/gnuradio/gr/runtime\_swig.py”, line 5607, in top\_block\_start\_unlocked return \_runtime\_swig.top\_block\_start\_unlocked(r, max\_noutput\_items) RuntimeError: audio\_alsa\_sink Now, if you simply restarted the application a _lot_ of times, it would occasionally “catch”, and it would run normally, without issue. So, I tried a smaller simpler app, using the same audio-sink parameters. It does the same as above, except _less frequently_ than the larger app. My suspicion is either a timing issue, or we have a memory stomper that is more likely to manifest in a larger flow-graph, and with timing and perhaps ASLR, you occasionally “sneak through”, and don’t provoke an “Invalid Argument” error way down deep in audio\_alsa. Sometimes with my larger flow-graph, I’d make a random change to it, like changing the taps on a filter a bit, and that would cause it to start working again slightly more frequently. Sure smells like a memory stomper… ☹ ☹