#12366 NORM 13.1.0: XO-4 24-bit sound playback is bad (was: XO-4 ogg vorbis files sound bad when played from gstreamer)

[Zarro Boogs per Child]

#12366: XO-4 24-bit sound playback is bad
---------------------------------+------------------------------------------
           Reporter:  Sunny Bao  |       Owner:  saadia       
               Type:  defect     |      Status:  new          
           Priority:  normal     |   Milestone:  13.1.0       
          Component:  kernel     |     Version:  not specified
         Resolution:             |    Keywords:               
        Next_action:  never set  |    Verified:  0            
Deployment_affected:             |   Blockedby:               
           Blocking:             |  
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Comment(by dsd):

 When ogg123 is running, /proc/asound/card0/pcm0p/sub0/hw_params is
 {{{
 access: RW_INTERLEAVED
 format: S16_LE
 subformat: STD
 channels: 2
 rate: 44100 (44100/1)
 period_size: 256
 buffer_size: 1024
 }}}

 but with gst-launch/playbin2 its:

 {{{
 access: MMAP_INTERLEAVED
 format: S24_LE
 subformat: STD
 channels: 2
 rate: 44100 (44100/1)
 period_size: 256
 buffer_size: 512
 }}}

 My immediate suspicion would be the mmap vs rw difference, but "aplay -M"
 is a simple mmap test and it does seem to work OK. The remaining
 differences in hw_params are format, period_size and buffer_size.

 Suspecting format, lets try Front_Center.wav from /usr/share/sounds/alsa.

 {{{
 sndfile-convert -pcm16 Front_Center.wav out.wav
 aplay out.wav # sounds fine

 sndfile-convert -pcm24 Front_Center.wav out.wav
 aplay out.wav # sounds bad

 sndfile-convert -pcm32 Front_Center.wav out.wav
 aplay out.wav # sounds bad
 }}}

 Both of those conversions result in S24_LE hw_params.

-- 
Ticket URL: <http://dev.laptop.org/ticket/12366#comment:3>
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