I think you should use speaker-test to test the various PCMs in aplay -L first, so that you can at least get a hint on whether it has something to do with ALSA or pulse. For example: [tom at localhost ~]$ speaker-test -D surround21:CARD=PCH,DEV=0 -c 3 -l 1 speaker-test 1.1.0 Playback device is surround21:CARD=PCH,DEV=0 Stream parameters are 48000Hz, S16_LE, 3 channels Using 16 octaves of pink noise Rate set to 48000Hz (requested 48000Hz) Buffer size range from 22 to 349525 Period size range from 11 to 174762 Using max buffer size 349524 Periods = 4 was set period_size = 87381 was set buffer_size = 349524 0 - Front Left 1 - Front Right 2 - LFE Time per period = 5.470904 [tom at localhost ~]$ speaker-test -D surround41:CARD=PCH,DEV=0 -c 5 -l 1 speaker-test 1.1.0 Playback device is surround41:CARD=PCH,DEV=0 Stream parameters are 48000Hz, S16_LE, 5 channels Using 16 octaves of pink noise Rate set to 48000Hz (requested 48000Hz) Buffer size range from 22 to 349525 Period size range from 11 to 174762 Using max buffer size 349524 Periods = 4 was set period_size = 87381 was set buffer_size = 349524 0 - Front Left 1 - Front Right 3 - Rear Right 2 - Rear Left 4 - LFE Time per period = 9.121826 [tom at localhost ~]$ speaker-test -D surround51:CARD=PCH,DEV=0 -c 6 -l 1 speaker-test 1.1.0 Playback device is surround51:CARD=PCH,DEV=0 Stream parameters are 48000Hz, S16_LE, 6 channels Using 16 octaves of pink noise Rate set to 48000Hz (requested 48000Hz) Buffer size range from 22 to 349525 Period size range from 11 to 174762 Using max buffer size 349524 Periods = 4 was set period_size = 87381 was set buffer_size = 349524 0 - Front Left 4 - Front Center 1 - Front Right 3 - Rear Right 2 - Rear Left 5 - LFE Time per period = 10.953665 [tom at localhost ~]$ I do feel like surround21.conf and surround41.conf is problematic though. I don't see why it should map LFE that way if it relys on surround51. It should be always "5 - LFE". I'll probably write to ALSA devel about it soon. On 16 January 2016 at 17:32, Nazar Mokrynskyi <nazar at mokrynskyi.com> wrote: > Noise appears when I test speaker in sound settings UI, so there is no > specific command. Also, when test sound stops - clicking doesn't. > I know it doesn't make sense, but it is what it is. > BTW, noise appears in target output, meaning even if I do not skip output, > but try to direct LFE to third output (one of rear speakers), there is no > sound there, only mentioned noise. > > Is it possible that sound card doesn't want to output low frequency sound on > other than default output, I mean some hardware/firmware limitation? > I'd be fine if LFE worked with 3rd output instead of 6th. > > Sincerely, Nazar Mokrynskyi > github.com/nazar-pc > Skype: nazar-pc > Diaspora: nazarpc at diaspora.mokrynskyi.com > Tox: > A9D95C9AA5F7A3ED75D83D0292E22ACE84BA40E912185939414475AF28FD2B2A5C8EF5261249 > > On 16.01.16 10:24, Tom Yan wrote: >> >> Sorry, I meant surround21. >> >> On 16 January 2016 at 17:21, Tom Yan <tom.ty89 at gmail.com> wrote: >>> >>> What do you mean by "noise in nth output starting from 1 instead, >>> relatively hight frequency light clicking"? How were you testing >>> exactly? speaker-test? if so what're the "-D"s you used? Can you paste >>> full commands (and maybe even the text output). >>> >>> What you said doesn't seem to make sense. If surround51 works, then >>> surround41 and surround20 should at most cause a signal/speaker >>> mismatch. I don't see how it can produce some weird noise/click. >>> >>> On 16 January 2016 at 16:26, Nazar Mokrynskyi <nazar at mokrynskyi.com> >>> wrote: >>>> >>>> OK, I've spent another hour or so trying different combinations and it >>>> seems >>>> to be a bug inside either ALSA or PulseAudio. >>>> SB Omni Surround 5.1, as you can see from name, has 6 outputs: >>>> front-left,front-right,rear-left,rear-right,front-center,lfe (lets >>>> ignore >>>> other non-related inputs/outputs here) >>>> I've done many experiments and defined which modes are working and which >>>> doesn't. >>>> >>>> Modes that work fine: >>>> - 5.1 >>>> - 5.0 >>>> - 4.0 >>>> - 2.0 >>>> >>>> Modes that doesn't work fine: >>>> - 2.1 (stereo only, noise in 3rd output starting from 1 instead, >>>> relatively >>>> hight frequency light clicking) >>>> - 4.1 (quadro only, noise in 5th output starting from 1 instead, >>>> relatively >>>> hight frequency light clicking) >>>> >>>> It is clearly visible that any time I want to skip some output, for >>>> instance: >>>> ttable.0.FL 1 >>>> ttable.1.FR 1 >>>> ttable.5.LFE 1 >>>> instead of >>>> ttable.0.FL 1 >>>> ttable.1.FR 1 >>>> ttable.2.LFE 1 >>>> >>>> To direct LFE to proper output it doesn't work. This is the same reason >>>> why >>>> 5.0 is working fine (no skipped outputs, all consequent) and 4.1 doesn't >>>> (we >>>> need to skip 5th output starting from 1 and use 6th instead). >>>> >>>> When I try this: >>>> ttable.0.FL 1 >>>> ttable.2.FR 1 >>>> ttable.1.LFE 1 >>>> then as expected I can hear LFE in right front output. >>>> >>>> Any hints from anyone what is wrong here? There are literally NO DOCS >>>> about >>>> how it works internally, so these experiments all I can provide at the >>>> moment. >>>> There were pulseaudio logs in this thread if anyone needs details. >>>> >>>> ALSA 1.1.0, PulseAudio 7.1, Ubuntu 16.04 x64 >>>> >>>> Sincerely, Nazar Mokrynskyi >>>> github.com/nazar-pc >>>> Skype: nazar-pc >>>> Diaspora: nazarpc at diaspora.mokrynskyi.com >>>> Tox: >>>> >>>> A9D95C9AA5F7A3ED75D83D0292E22ACE84BA40E912185939414475AF28FD2B2A5C8EF5261249 >>>> >>>> On 28.11.15 09:56, Raymond Yau wrote: >>>> >>>> >>>>> I've been looking at those lines. Do you think it should be done in >>>>> USB-Audio, or should it be added into separate config file specific for >>>>> this >>>>> sound card? >>>> >>>> >>>> http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=src/conf/pcm/surround21.conf;hb=HEAD >>>> >>>> The route of surround21 is hardcoded to use surround51 , this mean your >>>> ttable are used by those usb audio support 6 channels, those usb audio >>>> which >>>> only support 8 channels need to define their own 21 route as both >>>> surround51 >>>> and surround71 of usb audio use route plugin >>>> >>>> >>>> >>>> _______________________________________________ >>>> pulseaudio-discuss mailing list >>>> pulseaudio-discuss at lists.freedesktop.org >>>> http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss >>>> >>>> >>>> >>>> _______________________________________________ >>>> pulseaudio-discuss mailing list >>>> pulseaudio-discuss at lists.freedesktop.org >>>> http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss >>>> >> _______________________________________________ >> pulseaudio-discuss mailing list >> pulseaudio-discuss at lists.freedesktop.org >> http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss > > > > > _______________________________________________ > pulseaudio-discuss mailing list > pulseaudio-discuss at lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss >