Subject: kern/32718: choppy sound after mplayer pause/play, possibly kent-audio1 bug
To: None <,,>
From: Lubomir Sedlacik <>
List: netbsd-bugs
Date: 02/03/2006 12:45:01
>Number:         32718
>Category:       kern
>Synopsis:       choppy sound after mplayer pause/play, possibly kent-audio1 bug
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Feb 03 12:45:00 +0000 2006
>Originator:     Lubomir Sedlacik
>Release:        NetBSD 3.99.15
System: NetBSD 3.99.15 #0: Mon Jan 16 13:51:56 CET 2006 (but reported in 3.0 as well)
Architecture: i386
Machine: i386

from tech-kern@:

On Fri, Feb 03, 2006 at 02:28:24AM +0100, Rhialto wrote:
> I notice that audio playback in 3.0 is worse than in 2.0. In MPlayer I
> notice often that the sound is choppy after restarting from a pause.
> That hardly happened with 2.0.2.

i've noticed this as well.  i think it appeared after the kent-audio1
branch was merged.  i don't recall issues with any other application
than mplayer but it first started with just kernel updated so i don't
think it's a mplayer bug (at least it doesn't happen anywhere else i

i suspect it might be related to the way how mplayer pauses the sound
and then restarts it.

my soundcard:

auich0 at pci0 dev 31 function 5: i82801DB/DBM (ICH4/ICH4M) AC-97 Audio
auich0: interrupting at irq 5
auich0: ac97: Analog Devices AD1981B codec; headphone, 20 bit DAC, no 3D stereo
auich0: ac97: ext id 601<AC97_22,AMAP,VRA>

ident netbsd|egrep '(audio|auich)'

 $NetBSD: audio.c,v 1.199 2005/12/24 20:27:29 perry Exp $
 $NetBSD: auich.c,v 1.101 2005/12/04 12:27:49 xtraeme Exp $
 $NetBSD: ossaudio.c,v 1.49 2005/12/11 12:20:23 christos Exp $
 $NetBSD: uaudio.c,v 1.100 2005/12/11 12:24:01 christos Exp $

let me know if you need more debugging information, i am not sure what
else to add here and it should be fairly easy to reproduce.

apologies for not reporting it sooner..

- play a movie in mplayer
- pause/play (repeat if necessary)
- hear choppy sound
a workaround is to seek in the movie, skip ahead and back (or vice
versa), sound is back to normal