Misaligned Volume Sliders

[Dark Dragoon]

The problem I'm having is that the volumes do not appear to be aligned with each other.

For example if I set the volume to 0 in AlsaMixer the system volume drops to around 1/3. So the system volume has the volume set to 0 up to around the 30% mark.

If I try to adjust the volume in Rhythmbox the volume level almost immediately jumps to around 60% At around 50% in Rhythmbox the system volume is set to ~90%. If I set the system volume then go back and try to use Rhythmbox's volume control the volume gets set to 0%. The same happens with Totem.

This may be a silly question but with flat-volumes if I open PulseAudio Volume Control, should I still be able to set individual applications volumes? They still set the volumes independently so I can control the volume of individual applications however changing the system volume results in differences between applications.

For example both Rhythmbox's and Totem's volume control will change up and down with the system volume control, but if it gets set to zero Totem will stay at 0%, while Rhythmbox's will increase again.

I know I can disable flat-volumes, and this works fine.
echo "flat-volumes = no" >> /etc/pulse/daemon.conf

Although the system volume and the volume in AlsaMixer are still out of alignment. So just as before Rhythmbox's volume appears to also be misaligned so in PulseAudio Volume Control if the volume is set to 90% in Rhythmbox the slider moves to around 50%. The same hapens in Totem.


I was wondering if flat-volumes were working correctly for other people?
Or whether I have messed them up somehow.

I've had to use AlsaMixer to boost the volume as at the default settings it is very quiet

I have an Intel Corporation 82801G (ICH7 Family) High Definition Audio Controller (rev 02).
AlsaMixer reports the chip as a Realtek ALC272.

[youknowwho]

I'm having the same problem, it's weird, I don`t know if it's the intended functionality or its indeed a bug...oh well, after all, it's not a big deal, it's annoying but not a big deal.

[Dark Dragoon]

Yeah I agree it's not a huge issue, though when using headphones it's not particularly nice to have the volume jump to 100%. I'll just have to retrain myself to take the headphones off before attempting to change the volume.

[AdamW]

I'm finding it hard to figure out from your post exactly what it is you expect to happen, and what's actually happening.

It is intended that you can still set a per-application volume from within pavucontrol even wit flat volumes enabled, yes.

[Dark Dragoon]

Yeah rereading my post and it's not that clear.

From what I can tell there are two possibly three issues I'm having.

1) The ALSA volume doesn't match the PulseAudio volume and is out so that when the volume is set to 30% using the tray icon or volume controls on the keyboard it is actually at 0%. I've found a post which seems pretty much identical to what I'm experiencing: pulseaudio volume differs from alsa volume

2a) In pavucontrol the per-application volume appears to be working, however it still appears to be tied to the system volume. The volume for individual applications moves up and down when the system volume is changed via the tray icon. I'm not sure if this is by design, or whether they should stay as a percentage of the system volume.

2b) If the system volume is set to 0% then Totems (appears to be the background application, it occurs with Rhythmbox as well) application volume in pavucontrol will stay at 0% when the system volume is increased via the tray icon. Thus leaving the application muted even though I didn't touch it's individual volume control.

3) At this point Totems volume is at 0% both in pavucontrol and in Totem itself, the system volume has been increased to 60% using the tray icon causing Rhythmbox to have it's volume control set to 60% as well. If I now click on Totems volume control, but don't actually change the volume myself the system volume is set to 96% and Totems volume is also set to 96%.

Sorry if this is still a bit confusing.

[AdamW]

Thanks. I think I'll refer your post verbatim to Lennart; he'll be able to explain which of those are bugs and which aren't, and hopefully fix any problems

[AdamW]

OK, here's Lennart's explanation:

"Regarding 1):

This is by design. PA only looks for the dB scale of the hw mixer controls and then maps that to volume sliders (which usually range from 0% to 100% or suchlike) always the same way, even if the underlying hw would map it differently. The effect is that what PA refers to as 50% is different from what ALSA refers to as 50%. On top of that PA shifts the dB scale so that 0dB is always maximum hw amplification. Which means that ALSA's dB and PA's dB scale aren't necessarily the same either.

In summary: ignore the percentage scale. Look for dB only. But even then the scales won't match up in all cases.

Regarding 2a):

This is by design. It's the new flat volume logic. The device volume is always identical to the volume of the stream with the highest volume.

Regarding 2b):

This is known. It's due to the singularity of zero in context of the flat volume logic. We have been discussing a couple of ways to fix this. Nothing available in PA yet.

Regarding 3): If I understand the issue correctly this looks like a Totem bug to me."

So it looks like 2b and 3 are bugs; 2b is already known so you don't need to file it, but 3 you may want to file.

Thanks for your feedback!

[Dark Dragoon]

Thanks for the explanations,

I'm still a little confused with 1 as the system volume used to reduce down to nothing once it reached the minimum with Fedora 10 instead of a third the way up the slider. Not that this is a huge issue, though it makes the volume slightly harder to control.

As for 2a, that's fine and the explanation makes it easier for me to understand what's happening. The system volume will decrease by itself when I close the program that has the greatest volume set in pavucontrol.

If 2b is known then I'll wait for the fix for that one.

As for 3, I've been doing a bit more testing and I don't think it's a Totem bug as the same problem occurs with Rhythmbox. When I have some more time I'll test some other applications.

[AdamW]

for 1, in Fedora 10, PA didn't implement this dB-based volume control stuff yet, IIRC. I think if zero on the PA slider does not result in 'no sound', that's a bug, but if it shows at 30% on the ALSA slider but you can't actually hear anything, that's not a bug.

3 - could perhaps be something in gstreamer, then, as both Totem and RB are gstreamer-based?

[Dark Dragoon]

Here are some examples from both ALSA mixer Master and the PA Output Device, Internal Audio slider in pavucontrol:-

PA 100, ALSA 100 (dB gain = -0)
PA 90, ALSA 88 (dB gain = -9)
PA 80, ALSA 72 (dB gain = -18)
PA 70, ALSA 58 (dB gain = -27)
PA 60, ALSA 45 (dB gain = -35)
PA 50, ALSA 30 (dB gain = -45)
PA 40, ALSA 17 (dB gain = -54)
PA 30, ALSA 2 (dB gain = -63) At this point there is 'no sound'
PA 20, ALSA 0 (dB gain = -64)
PA 10, ALSA 0 (dB gain = -64)
PA 0, ALSA 0 (dB gain = -64)

Is this a bug then, as zero on the PA slider does indeed result in no sound, as does ~1/3 on the PA slider.
When the ALSA slider hits 0 or dB gain= -64 there is no sound.


As for 3 I haven't been able to reproduce exactly the same issue with VLC and the Gnome front end to MPlayer yet though there is an odd situation where if I reduce the volume down to 0 then increase it via the PA tray icon the applications remain muted as with the other applications. However I am unable to increase their volumes either from within the program (not that I expected to be able to do this using VLC) or by using pavucontrol which shows the slider as greyed out and is overall unresponsive e.g. cannot change tabs, cannot close pavucontrol etc..., though I can see the volume levels changing, so it appears to be only the GUI that's locked.

[AdamW]

it does look a bit badly calibrated, i would expect the PA slider to scale smoothly from -64 to 0. Probably worth filing a bug on that - include the info from this thread, and alsa-info.sh report for your card, component should be pulseaudio. thanks!

[Dark Dragoon]

I have created a bug report for the volume scaling (502057), and the other problems stop occurring when I disable flat-volumes so I'll leave it set that way for the time being.

In addition to the laptop I've been finding these issues on, I've just installed Fedora 11 on another older laptop with very different hardware. I'm seeing a similar problem with regards to the calibration.

PA 100, ALSA 100 (dB gain = -0)
PA 90, ALSA 81 (dB gain = -9)
PA 80, ALSA 61 (dB gain = -18)
PA 70, ALSA 45 (dB gain = -27)
PA 60, ALSA 23 (dB gain = -36)
PA 50, ALSA 3 (dB gain = -45) At this point there is almost 'no sound'
PA 40, ALSA 0 (dB gain = -46.5)
PA 30, ALSA 0 (dB gain = -46.5)
PA 20, ALSA 0 (dB gain = -46.5)
PA 10, ALSA 0 (dB gain = -46.5)
PA 0, ALSA 0 (dB gain = -46.5)

Should I report this as a new bug, add it to the existing bug report or wait and see what happens to the exiting bug report first?

The audio is reported as:
Card: VIA 8235
Chip: Via Technologies VIA1612A

[AdamW]

Wait and see what happens to the first report, I think.

[Dark Dragoon]

Hmm so it's been closed as not being a bug.

I've found another bug report which is pretty much identical to the problem I've been having with the two computers I've been testing Fedora 11 on. I might just wait and see what happens to that bug (499719).

[AdamW]

well, the explanation of why it's not a bug sounds sensible to me - it doesn't look like a brush-off. it seems PA really does provide a smooth range, but it's extended below -64dB in software in PA, so you don't see that in alsamixer.