Sound probem using optical out from the card.

John_82 john_82 at
Sun Mar 12 15:24:53 GMT 2017

On Sat, 11 Mar 2017 23:22:42 -0600
Joel Koreth <joelsymon at> wrote:

> On Saturday, March 11, 2017 8:50:25 AM CST John_82 wrote:
> > This can be avoided by commenting out the user pulse idle timer module load
> > so that it stays loaded. I'm using the optical output on a creative
> > titanium xfi hd for stereo. Now this is out I just get a grunt when I log
> > into the desktop and sound is activated. Louder and longer then the usual
> > one when the pc gets up and running from boot. )-: at least I don't get the
> > coming in and dropping out noises any more.
> > 
> > Frome one comment elsewhere others may be getting the same thing
> > particularly via web pages. Described as clicks. Could be optical is worse.
> > 
> > John
> > -
> > 
> > On Thu, 9 Mar 2017 11:27:06 +0000
> > 
> > John_82 <john_82 at> wrote:
> > > I've just upgraded from a middling kde4 to kde 5.26. opensues leap 42.2
> > > 
> > > I get grunts before any sound plays and another later when the sound
> > > service drops out. Web page updates sometimes cause them too, sort oh we
> > > may need sound problem by the look of it as they don't always generate
> > > any sound so just get the grunt and later another when sound drops out.
> > > 
> > > The problem may be that phonon isn't offering me a digital output only an
> > > iec958 one.  Leap's YAST sound set up utility shows 2 aux volumes, one
> > > for iec958 and another for digital. Sound's fine here. The iec one
> > > doesn't do anything. I also tried my system via a bootable Knoppix iso
> > > with lxde. Same there. It appears to use alsa from top to bottom and the
> > > mixer shows both volume controls. Only digital does anything and no sound
> > > problems
> > > 
> > > The other reason may be a note in the pulse conf file. No static loads in
> > > one section, use udev-detect instead.
> > > 
> > > My kde4 didn't have this problem only the youtube volume messing up the
> > > desktop volume and deafening everybody. I notice something which seems to
> > > over ride that one in 5.
> > > 
> > > Tracking back the card is being detected correctly and getting the correct
> > > driver so all should be ok. Trying to sort out the set up past this
> > > though is way past me - masses of directories etc.
> > > 
> > > ??? Why an application volume control from the panel??? All apps I use
> > > have one. My keyboard has one too so guess which one I am inclined to use
> > > - ;-) Just a moan.
> > > 
> > > John Please excuse any typo's. I make odd ones.
> > > -
> Sorry I know this is late but did you check Audio Volume -> Configuration and 
> turning analog output off and just relying on digital output? I may be 
> misunderstanding your problem though.
I had tried that sort of thing but from kde's settings-multimedia- no luck. At one point I installed pavucontrol so just gave it a go there. It retains a muted analogue output on the card leaving the digital as it was but then no sounds in kde. Changing things in that produces the same sort of noises I get when a sound starts playing and shortly after it's finished. It's stopping pulse and then starting it again.

My conclusion is that the problem is purely down to pulse's idle time out and doesn't happen in say YAST because it doesn't allow it to time out. The oddities about the aux volume controls are a red herring. It could be the the protocol needed by the card is different and was ok on kde4 and iec958 is different in some way. There is also a comment in about a module being needed if pulse  is stopped completely when not needed. I do have it installed. An idle time out looks to be different though or why have both.

One good thing is that going on ksysguard output preventing it from timing out doesn't show any increase in cpu load at all that I can see. Playing music is much the same except when it starts.

I spent some time playing with alsa bits and pieces. Conclusion - they generally don't do anything anymore. There isn't any mechanism that I could find other than phonon on the desktop to see or change exactly what kde is getting up to. ;-) I'm almost reminded of windoze. I did manage to trace from pci up to the desktop. No chance past that.


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