Bug 41342

Summary:	Audio gain is massively higher in kernel 3.1
Product:	Drivers	Reporter:	rocko (rockorequin)
Component:	Sound(ALSA)	Assignee:	Jaroslav Kysela (perex)
Status:	CLOSED CODE_FIX
Severity:	normal	CC:	florian, maciej.rutecki, rjw, tiwai
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	3.0-rc2	Subsystem:
Regression:	Yes	Bisected commit-id:
Bug Depends on:
Bug Blocks:	40982
Attachments:	alsa-info.txt Fix patch

Description rocko 2011-08-18 08:12:58 UTC

The audio volume is much, much louder in 3.1-rc2 and -rc1 compared to kernel 3.0 and earlier for my card:

00:1b.0 Audio device: Intel Corporation 6 Series Chipset Family High Definition Audio Controller (rev 05)
	Subsystem: Dell Device 050e
	Flags: bus master, fast devsel, latency 0, IRQ 53
	Memory at f1c00000 (64-bit, non-prefetchable) [size=16K]
	Capabilities: <access denied>
	Kernel driver in use: snd_hda_intel
	Kernel modules: snd-hda-intel


Sound blasts out deafeningly unless I use alsamixer to adjust Master to zero (alsamixer says this is -64dB) and PCM to near to zero (eg a value like 27, ie -29dB).

Note that with kernel 3.0, adjusting PCM in alsamixer does not affect the sound gain, but in 3.1 it (luckily!) does. It's quite difficult to adjust the sound to a non-painful level using gnome-volume control because the gain is biased so high.

Comment 1 Takashi Iwai 2011-08-18 09:39:47 UTC

Please give alsa-info.sh output (run with --no-upload option).

Comment 2 rocko 2011-08-18 11:26:23 UTC

Created attachment 69262 [details]
alsa-info.txt

Comment 3 Takashi Iwai 2011-08-18 12:18:29 UTC

Thanks.  The bug is that Master volume isn't linked with PCM volume, thus Master is just a noop in the new driver.  The 

Try the patch below.

Comment 4 Takashi Iwai 2011-08-18 12:19:10 UTC

Created attachment 69272 [details]
Fix patch

Comment 5 rocko 2011-08-18 14:19:22 UTC

Thanks, that fixes it.

Comment 6 Takashi Iwai 2011-08-18 14:48:33 UTC

OK, the patch is included in sound git tree now.  It'll be merged likely in 3.1-rc3.

Comment 7 Florian Mickler 2011-08-23 20:18:55 UTC

A patch referencing this bug report has been merged in Linux v3.1-rc3:

commit 3fe45aeaf2033c9eaa5028ed5ba68b466008876f
Author: Takashi Iwai <tiwai@suse.de>
Date:   Thu Aug 18 15:13:17 2011 +0200

    ALSA: hda - Add "PCM" volume to vmaster slave list