Arch Linux

jbromley

Member

From: Pasadena, CA

Registered: 2007-02-04

Posts: 268

Set audio channel controlled by multimedia buttons

In KDE, is there a way I can set the audio channel that is controlled by the multimedia buttons? I am having a problem where the raise and lower volume buttons are not controlling the correct (PCM) channel.

I have a Dell Inspiron 9300 with the Intel AC'97 audio controller. The computer has normal speakers, controlled by the Master channel and a subwoofer controlled by the Master Mono channel. Because of this, in kmix, I leave the two above channels set and use the PCM control to control overall volume, as adjusting the "Master" channel does not affect subwoofer volume. Now, when I use kmix to adjust volume, things are fine, however when I use the multimedia raise/lower volume buttons, only the Master channel gets adjusted. I assume there must be some place where the channel controlled by these buttons can be set, but I cannot find it. I believe I've read that kmilo handles this task, but I cannot find where I might configure that.

I would be willing to do some hacking of the appropriate code, if it is required. Someone would just have to point me to what library/executable contains the code that handles the mentioned multimedia buttons.

Thanks and regards,
jbro

Mikko777

Member

From: Suomi, Finland

Registered: 2006-10-30

Posts: 837

Re: Set audio channel controlled by multimedia buttons

This sounds similar to what i've got.

So if you use alsa you could write an asound.conf with softvol mixer and route all your channels to that.
Then the softvol mixer can replace any existing control like master or pcm.

It's easier than it sounds, check example configs in alsa wiki, search for softvol.

Hope that helps.

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Planet KDE | Opendesktop.org | Chakra Project

jbromley

Member

From: Pasadena, CA

Registered: 2007-02-04

Posts: 268

Re: Set audio channel controlled by multimedia buttons

Thanks for the suggestion, but that is actually one thing I tried with no luck. I could create a "Soft Master" channel and use it to control overall volume, the same as just selecting PCM as the master channel, but the multimedia keys still directly changed the "Master" channel. Note that I have no problem when changing the volume through kmix. It properly adjusts the PCM channel, which I have set as the master channel. Only when I press the multimedia keys do I have this problem, so it looks like kmilo isn't paying attention to the master channel and automatically adjusting the first channel. Unfortunately, according to the ALSA wiki, there is no way to override an existing channel.

...

OK, I took a look at the latest code (KDE 4.0) for the delli8k plugin for kmilo and it adjusts "masterVolume" via dcop. When I do the corresponding commands from a prompt everything works fine. This leads me to believe that KDE 3.5.7 doesn't have the code I'm looking at. This is odd, though, as the last change in the Dell kmilo plugin was in September of last year. Perhaps it has not been backported to KDE 3.5.7. When I get some time I will try to compile the new kmilo and plugins to see if that changes anything.

Thanks again for the suggestion.

pauldonnelly

Member

Registered: 2006-06-19

Posts: 776

Re: Set audio channel controlled by multimedia buttons

My solution was to write scripts named vol+ and vol- that set my front and rear speakers to appropriate levels and bind those with xbindkeys.

jbromley

Member

From: Pasadena, CA

Registered: 2007-02-04

Posts: 268

Re: Set audio channel controlled by multimedia buttons

My solution was to write scripts named vol+ and vol- that set my front and rear speakers to appropriate levels and bind those with xbindkeys.

Yes, in the past I did something siimilar. In that case, you lose the visual feedback on the volume levels, though. Unless your script displays the current volume. I used xosd or osdsh to provide visual confirmation of the volume level. I just would like everything to work through KDE. Once everything else on this machine is set up I plan to set up a KDE development environment, so I guess once I do that I can build the correct version of the code and that should fix the problem.

Thanks and regards.

dka

Member

From: Russia, Saint-Petersburg

Registered: 2007-03-10

Posts: 10

Re: Set audio channel controlled by multimedia buttons

read archlinux wiki and correct your /etc/acpi/handler.sh

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Sorry for my english

jbromley

Member

From: Pasadena, CA

Registered: 2007-02-04

Posts: 268

Re: Set audio channel controlled by multimedia buttons

read archlinux wiki and correct your /etc/acpi/handler.sh

¿? The multimedia keys on a Dell already generate the valid XF86Audio* keysyms which are processed by KMilo and others. They do not generate ACPI events. Would you mind elaborating a bit, maybe I'm missing something here?

Thanks.