[pulseaudio-tickets] [PulseAudio] #435: severe and frequent stuttering

[PulseAudio]

#435: severe and frequent stuttering
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  Reporter:  brian_j_murrell  |       Owner:  lennart
      Type:  defect           |      Status:  new    
  Priority:  normal           |   Milestone:         
 Component:  daemon           |    Severity:  major  
Resolution:                   |    Keywords:         
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Comment (by lennart):

 Replying to [comment:4 brian_j_murrell]:

 > I'm certainly not doubting you on this, but for the record of this
 ticket and anyone else who comes across it, why does it work so well with
 just plain ALSA driving it?

 We schedule audio with timer interrupts, not with sound card interrupts --
 which we disable as much as possible. That allows us to variably change
 the wakeup frequency to match what clients that come and go need. This
 kind of scheduling requires the sound driver to provide us with correct
 timing information so that we can properly estimate the wakeup times. This
 is broken in the emu10k driver which causes PA to miscalculate the wakeup
 times based on this wrong data and thus missing the deadlines which you
 can hear as dropouts.

 As long as you only play MP3 music directly on the device and use the
 traditional sound card interrupt based wakeups the bogus timing
 information the sound drivers export doesn't matter. That's why you won't
 notice this issue without PA but it becomes very visible (or audible...)
 when PA is used.

 > as my main audio sound card.  Will I have better luck with that device
 and PA?

 HDA is pretty well supported. Docs are open. A lot of hw has bugs but
 those can usually be worked around. Usually support for HDA should be
 pretty good, and if it isn't it is quickly fixed.

-- 
Ticket URL: <http://www.pulseaudio.org/ticket/435#comment:6>
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