master output scale is messed up

[Dean Henrichsmeyer]

In precise, I don't hear any sound unless I have the volume turned half way up. It's like the entire volume range is contained with the 50% to 100% range. The end result is small changes in volume make drastic changes. In both natty and oneiric, the volume scaled linearly coordinating with the slider.

This is similar to #579290 but the reverse.

Also, I believe I'm actually losing volume. The master turned all the way up is not nearly as loud as it was under previous releases.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: pulseaudio 1:1.1-0ubuntu4
ProcVersionSignature: Ubuntu 3.2.0-7.13-generic 3.2.0-rc7
Uname: Linux 3.2.0-7-generic x86_64
NonfreeKernelModules: fglrx
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 1.90-0ubuntu1
Architecture: amd64
Card0.Amixer.info:
 Card hw:0 'PCH'/'HDA Intel PCH at 0xfe700000 irq 45'
   Mixer name : 'Intel CougarPoint HDMI'
   Components : 'HDA:10ec0887,102804aa,00100302 HDA:80862805,80862805,00100000'
   Controls : 40
   Simple ctrls : 21
Card1.Amixer.info:
 Card hw:1 'U0x46d0x809'/'USB Device 0x46d:0x809 at usb-0000:00:1d.0-1.3, high speed'
   Mixer name : 'USB Mixer'
   Components : 'USB046d:0809'
   Controls : 2
   Simple ctrls : 1
Card1.Amixer.values:
 Simple mixer control 'Mic',0
   Capabilities: cvolume cvolume-joined cswitch cswitch-joined penum
   Capture channels: Mono
   Limits: Capture 0 - 17
   Mono: Capture 12 [71%] [23.64dB] [on]
Card2.Amixer.info:
 Card hw:2 'Generic'/'HD-Audio Generic at 0xfe640000 irq 46'
   Mixer name : 'ATI R6xx HDMI'
   Components : 'HDA:1002aa01,00aa0100,00100200'
   Controls : 5
   Simple ctrls : 1
Card2.Amixer.values:
 Simple mixer control 'IEC958',0
   Capabilities: pswitch pswitch-joined penum
   Playback channels: Mono
   Mono: Playback [on]
Date: Fri Jan 6 10:31:12 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
SourcePackage: pulseaudio
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/15/2011
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A03
dmi.board.name: 0Y2MRG
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 3
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA03:bd02/15/2011:svnDellInc.:pnXPS8300:pvr:rvnDellInc.:rn0Y2MRG:rvrA00:cvnDellInc.:ct3:cvr:
dmi.product.name: XPS 8300
dmi.sys.vendor: Dell Inc.

[David Henningsson (diwic)]

Hi Dean,

1) Could you clarify whether this applies to headphones, speakers, line-outs or all of them?

2) Open a terminal window and execute the command "alsamixer -D hw:PCH". While moving the master slider (in the indicator, or sound settings applet), sliders in alsamixers will move as well. Can you figure out what slider that it is that moves in the range where nothing is happening to the output volume?

[Dean Henrichsmeyer (dean)]

Only the master slider moves when I turn the volume up and down with the keyboard keys. No sound is audible unless the master is at 42% (6.75 dB gain) so the entire range of audio is between 42 and 100%.

It happens the same when I plug headphones in.

Now, If I max the master mixer at 100% and use the headphone mixer in alsamixer the scale is linear as it should be meaning I have the full range. It's just the master mixer that is missing roughly half the range.

After doing that, the onscreen volume indicator doesn't match the real mixer level and therefore hitting the volume +/- keys on the keyboard really mess with the mixers (PCM mixer alternates between 96-100 for a while and then the master starts being affected, etc)

Sorry if my description didn't help, but it's really broken. I would blame just the onscreen indicator but that's not really the problem because you get the same behavior if you use the master mixer in alsamixer. Let me know if I can provide any more details, happy to do whatever.

[Dean Henrichsmeyer (dean)]

So this is fixed in precise for me at the moment. I'm currently running a mainline kernel (3.3.0-030300rc2-generic) but other than that I'm stock precise.

[Dean Henrichsmeyer (dean)]

More information. Today I reverted to a different mainline kernel to test a different bug and the scale problem is back. I'm using 3.2.7-030207-generic.

It looks like this bug is due to the 3.0 and 3.2 series of kernels as it works fine in 3.3.0 and 2.6.*

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Dean Henrichsmeyer (dean)]

I believe this is actually a kernel issue that's now fixed.