[gentoo-user] sound stuttering, breaking up, fading in and out

[Chris Spackman]

I have an issue with sound during music and sometimes video
playback. Usually it fades out (gets quieter) and then fades back in a
couple of seconds later. This happens randomly maybe a couple of times
in an hour or two, but can sometimes go several hours without
issue. It has happened with quodlibet and mocp (audio - mostly ogg,
some mp3) and with vlc (video - mostly mp4/m4v). I don't use other
music/video software enough to notice it there.

During heavy load (like emerging packages), the sound will sometimes
stutter or even stop and then restart a few seconds later. The
computer is a few years old, but this has not happened in the past.

I found somewhere the suggestion to add the following options to
/etc/modprobe.d/sound.conf

options snd-hda-intel vid=8086 pid=8ca0 snoop=0

The fading out/in *seems to be* less frequent since doing that. But
that is my subjective feeling, not based on data.

Any ideas on what might be wrong and how it can be fixed?

** System **

Window Manager = PekWM

kernel = Linux sys76 3.18.11-gentoo #1 SMP PREEMPT Thu Apr 9 13:56:02 EDT 2015 x86_64 Intel(R) Core(TM)2 Quad CPU Q8400 @ 2.66GHz GenuineIntel GNU/Linux


** Hardware Info **

lspci reports:
Audio device: Intel Corporation 82801JI (ICH10 Family) HD Audio Controller

Modules, from lsmod | grep snd:

snd_hda_codec_idt      39744  1
snd_hda_codec_generic    39746  1 snd_hda_codec_idt
snd_hda_intel          17007  2
snd_hda_controller     13712  1 snd_hda_intel
snd_hda_codec          68033  4
snd_hda_codec_idt,snd_hda_codec_generic,snd_hda_intel,snd_hda_controller
snd_hwdep               5373  1 snd_hda_codec
snd_pcm                63521  3
snd_hda_codec,snd_hda_intel,snd_hda_controller
snd_timer              15422  1 snd_pcm
snd                    49995  11 snd_hwdep,snd_timer,snd_hda_codec_idt,snd_pcm,snd_hda_codec_generic,snd_hda_codec,snd_hda_intel

** Software **

[I] media-sound/pulseaudio

          Installed versions:  5.0-r7(03:35:44 PM 04/08/2015)(X alsa
     alsa-plugin asyncns bluetooth caps dbus gdbm glib gtk ipv6 orc
     qt4 ssl tcpd udev webrtc-aec -doc -equalizer -gnome -jack
     -libsamplerate -lirc -neon -oss -realtime -system-wide -systemd
     -test -xen -zeroconf ABI_MIPS="-n32 -n64 -o32" ABI_PPC="-32 -64"
     ABI_S390="-32 -64" ABI_X86="64 -32 -x32")
     
[I] media-plugins/gst-plugins-pulse

          Installed versions:  0.10.31-r1(0.10)^t(12:55:06 PM
     04/11/2015)(ABI_MIPS="-n32 -n64 -o32" ABI_PPC="-32 -64"
     ABI_S390="-32 -64" ABI_X86="64 -32 -x32") 1.4.5(1.0)^t(04:27:00
     PM 04/05/2015)(ABI_MIPS="-n32 -n64 -o32" ABI_PPC="-32 -64"
     ABI_S390="-32 -64" ABI_X86="64 -32 -x32")
     
[I] media-sound/moc

          Installed versions:  2.5.0(05:50:51 PM 04/12/2015)(aac alsa
     cache ffmpeg flac mad magic unicode vorbis -curl -debug -jack
     -libsamplerate -modplug -musepack -oss -sid -sndfile -speex
     -timidity -tremor -wavpack)

(I removed Quodlibet recently for unrelated reasons.)

Thanks for any and all help and advice.

-- 
Chris Spackman

GNU Terry Pratchett