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I've a C-Media sound card - CM8738 and 5.1 speakers.

Everything seems to work pretty good, but there is a problem - two speakers are mixed - subwoofer is a central speaker, and central speaker is a subwoofer for Ubuntu.

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1- Run in terminal gksu gedit /usr/share/pulseaudio/alsa-mixer/profile-sets/default.conf This is the file where the channel map is, enter you pasword when prompted, and the file will open.

2- You are looking for the code that looks like this-

[Mapping analog-surround-51]
 device-strings = surround51:%f
 channel-map = front-left,front-right,rear-left,rear-right,front-center,lfe
 paths-output = analog-output analog-output-speaker analog-output-desktop-speaker analog-output-lfe-on-mono
 priority = 8
 direction = output

3- It may not be exactly the same, but we want to change only the channel-map order
from -
channel-map = front-left,front-right,rear-left,rear-right,front-center,lfe
to -
channel-map = front-left,front-right,rear-left,rear-right,lfe,front-center

Notice the order on lfe and front-center, lfe is the subwoofer, and front-center is your center speaker, if it displays another configuration, just swap position of lfe and front-center


Let me know how this works for your version.

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Now pulseaudio don't want to work. Sound settings don't see any sound card. – user57249 Apr 28 '12 at 6:57
I did. Ubuntu 12.04, but it didn't worked on previous versions also. I don't have amplituner, it's normal sound system from Creative so I guess, I will have to buy new sound card. Bad news. But I still have some hope. – user57249 Apr 28 '12 at 20:39
It is probably not possible to map output jacks as input jacks with this method, is it? I tried, but the mic still seems not to be connected/existing in the Unity audio settings... – Byte Commander May 4 '15 at 9:19

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