I have a Core 2 Duo Macbook
Code:
hunter@hunter-laptop:~$ sudo dmidecode | grep Mac
Product Name: MacBook3,1
Family: MacBook
Product Name: Mac-F22788C8
Version: Mac-F22788C8
with the following audio card:
Code:
hunter@hunter-laptop:~$ lspci | grep Audio
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)
My problem is that the audio is very poor quality in Ubuntu 8.04. It is especially noticeable at high volumes (over 50%). It sounds very tinny, like a really cheap hand-held radio. The audio sounds fine in OS X, so it is a Linux problem. After a lot of research I have found two possible explanations. I do not know if either of these is actually causing the problem, just that someone has stated they could be.
1. There is a hardware equalizer that ALSA cannot take advantage of, which is causing the distortion.
2. There is a third speaker for low frequency sound which is not being utilized.
Running speaker-test:
Code:
hunter@hunter-laptop:~$ speaker-test -c8 -twav -l 1
speaker-test 1.0.15
Playback device is default
Stream parameters are 48000Hz, S16_LE, 8 channels
WAV file(s)
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 2048 to 16384
Period size range from 1024 to 1024
Using max buffer size 16384
Periods = 4
was set period_size = 1024
was set buffer_size = 16384
0 - Front Left
4 - Center
1 - Front Right
7 - Side Right
3 - Rear Right
2 - Rear Left
6 - Side Left
5 - LFE
Time per period = 11.050963
I only hear front left and front right, so I assume it is not explanation #2. I have tried several solutions, which have all failed, including (but not limited to):
- Implementing a system wide PulseAudio equalizer (following a howto on the forums.)
- Adding various lines to /etc/modprobe.d/alsa-base and /etc/modprobe.d/options including:
install snd-hda-intel position_fix=1 /sbin/modprobe --ignore-install snd-hda-intel $CMDLINE_OPTS && { /lib/alsa/modprobe-post-install snd-hda-intel ; }
options snd_hda_intel model=mbp3
options snd_hda_intel model=intel-mac-v1 (through v5)
options snd_hda_intel model=macbook
- Adjusting the surround setting in alsa-mixer (which only shows up when the sound isn't working.)
The only of the lines above to work were the first two. And the first one only works when the second is present, so I assume it doesn't matter.
Please help me, this terrible audio is driving me crazy.