[MacBookPro8,1, CS4206] Left speaker low volume and absence of low freqs

Bug #1234252 reported by Vladimir Katilevskiy on 2013-10-02
This bug affects 4 people
Affects Status Importance Assigned to Milestone
alsa-driver (Ubuntu)

Bug Description

Ubuntu 13.04 fresh install or fully updated - no difference.
While listening music through internal speakers I noticed that left speaker sounds differently from the right one. I would describe left speaker's sound as those from the headphones lying on the table: low volume level and mostly high frequences are heard.
1) Trying to check mixer levels in alsamixer, muting/unmuting, balance channels etc didnt help.
2) In alsamixer there is a mixer item called "Bass Speaker". If I mute it, other playback items (including Master) are muted too. If I make its level to 0, then sound from both speakers become identical: low volume and without bass frequences. Level of the Bass Speaker resets if I adjust volume level from Unity volume control tool.
3) Trying to set model parameter for intel_hda module to "mbp55" or "imac27" didnt help.
4) Sound from headphones is perfectly ok.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: alsa-base 1.0.25+dfsg-0ubuntu4
ProcVersionSignature: Ubuntu 3.8.0-19.29-generic 3.8.8
Uname: Linux 3.8.0-19-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.9.2-0ubuntu8
Architecture: amd64
 /dev/snd/controlC0: vkat 1970 F.... pulseaudio
 /dev/snd/pcmC0D0c: vkat 1970 F...m pulseaudio
Date: Wed Oct 2 19:12:40 2013
InstallationDate: Installed on 2013-10-02 (0 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:PCH failed
Symptom_Card: Built-in Audio - HDA Intel PCH
Symptom_Jack: Speaker, Internal
Symptom_Type: High background noise, or volume is too low
Title: [MacBookPro8,1, Cirrus Logic CS4206, Speaker, Internal] Background noise or low volume
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 01/24/12
dmi.bios.vendor: Apple Inc.
dmi.bios.version: MBP81.88Z.0047.B27.1201241646
dmi.board.asset.tag: Base Board Asset Tag#
dmi.board.name: Mac-94245B3640C91C81
dmi.board.vendor: Apple Inc.
dmi.board.version: MacBookPro8,1
dmi.chassis.type: 10
dmi.chassis.vendor: Apple Inc.
dmi.chassis.version: Mac-94245B3640C91C81
dmi.modalias: dmi:bvnAppleInc.:bvrMBP81.88Z.0047.B27.1201241646:bd01/24/12:svnAppleInc.:pnMacBookPro8,1:pvr1.0:rvnAppleInc.:rnMac-94245B3640C91C81:rvrMacBookPro8,1:cvnAppleInc.:ct10:cvrMac-94245B3640C91C81:
dmi.product.name: MacBookPro8,1
dmi.product.version: 1.0
dmi.sys.vendor: Apple Inc.

affects: alsa-driver (Ubuntu) → linux-meta (Ubuntu)
Brad Figg (brad-figg) on 2013-10-02
affects: linux-meta (Ubuntu) → linux (Ubuntu)
Joseph Salisbury (jsalisbury) wrote :

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.12 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.12-rc3-saucy/

Changed in linux (Ubuntu):
importance: Undecided → Medium
status: New → Incomplete

Joseph, thanks for the answer.
Have just tried latest 3.12 kernel, but the bug is still there :(
I ll try to use hda-analyzer tool from alsa-project just to see what happening when I move the Bass speaker slider in alsamixer. It seems to me, that only right channel' slider of this mixer item works, while left always stays at 0, regarless of slider position.

tags: added: kernel-bug-exists-upstream
Changed in linux (Ubuntu):
status: Incomplete → Confirmed

Well, hda-analyzer tool running in monitor mode shows that volume level of Bass speaker changes while moving corresponding sliders (left and right) in alsamixer, but those changes affect only right channel.
Feel free to ask me for additional info/logs or for triyng defferent versions of kernel etc.
I can ever totally ruin current installation with no sorrow, cause my main goal now is to struggle that bug and make ubuntu my main OS on that laptop.
Thank you for your help.

Raymond (superquad-vortex2) wrote :

take a look at cs4207 datasheet


It seems I found the answer to my question/bugreport.
My macbook pro 8.1 13-inch really has 3 speakers: left, right and so called (by Apple) "subwoofer" - standalone additional speaker, which is located on the right side (this is important!). It is a really new thing for me (after 2 years of using laptop).
So alsamixer (and intel-hda driver) is absolutely correct naming one of the controls as "Bass speaker".
Other items in alsamixer are: Master, Speaker, Headphone and PCM.
Now the important thing: if I set to 0 right channel of Speaker in alsamixer, the left sounds like it was in Mac OS in the same mode (balance shifted to left speaker) - that is the right way how the balance should work!
But balance slider in Ubuntu sound panel (let's call it slider U) works very strange: at first, when i start to move it to the left - alsamixer's Speaker right channel (slider A) goes down as it should be. But when slider U is approx. 5% till the end, slider A is already 0! At this point the sound is ok (coming from left speaker, but with bass as it should be).
And if I continue to move slider U till the end, I see right PCM going down dramatically fast in alsamixer. And now the sound is incorrect (as stated in my bugreport).

So I can say that when in normal mode (balance set to 50/50) the sound is ok and identical to Mac OS.
The questions are:
1) Why does ubuntu's sound panel (and pavucontrol too) treat subwoofer speaker as the right one?
2) Why does ubuntu's sound panel balance slider behave in such strange way (described above)?
2) Why is the subwoofer speaker included in right channel of PCM control (in alsamixer)?

Overall, I am happy to solve this puzzle (the answer looks so simple if to look back). Please tell me, should I post a new report(s) or leave it as is?
And sorry for my Russian English :)

affects: linux (Ubuntu) → alsa-driver (Ubuntu)
Tai Tran (sentient-style) wrote :

i'm not an expert, but i did have sound problems installing Windows OS in EFI mode.

Did you try booting into the normal CD when installing linux? (If you did it by USB then it probably was EFI mode, since macbooks can only boot that way from them.)
*There's usually two options when booting into CD, when you hold alt/option at startup

Not that i've tried it, but it might be what is causing it.

monochromec (monochromec) wrote :

Same situation in 14.10.

Is anybody upstream looking at this?

Luca Ciavatta (cialu) wrote :

Same issue on MacBook Pro 8,2 with Ubuntu 16.04 and Ubuntu 16.10.

To post a comment you must log in.
This report contains Public information  Edit
Everyone can see this information.

Other bug subscribers