[-Bender-]

hello, ive been using slack 10 and a 2.4.xx kernel for a bit now and it has came to my attention that i can't have two application both using my audio device(ac97 on boad sound using the alsa module) simontaneously. I can only have one application using it at a time. Anyone know how to fix this cause it would be nice to listening to music and play a game that needs to use audio.
Thanks Benny,

[short101]

Look at jack. There is another plugin that I cant remember at the moment. Basically lets you share the card between two apps.

[tsunam]

create a dmix that you use to take the input from multiple sources and combine them into one stream.

for example my .asoundrc

pcm.dmixer {
        type dmix
        ipc_key 1024
        slave {
                pcm "hw:0,0"
                period_time 0
                period_size 1024
                buffer_size 8192
        rate 44100
        }

        bindings {
                0 0
                1 1
        }
}

pcm.dsp {
        type plug
        slave.pcm "dmixer"
}

ctl.mixer0 {
        type hw
        card 0
}

[-Bender-]

Thanks for the replys, i put this is my ~/.asoundrc

pcm.ossmix {
    type dmix
    ipc_key 1024          # must be unique!
    slave {
        pcm "hw:0,0"      # you cannot use a "plug" device here, darn.
        period_time 0
        period_size 1024  # must be power of 2
        buffer_size 8192  # dito. It
        #format "S32_LE"
        #periods 128      # dito.
        #rate 8000        # with rate 8000 you *will* hear, 
                          # if ossmix is used :)
    }

# bindings are cool. This says, that only the first
# two channels are to be used by dmix, which is enough for
# (most) oss apps and also lets multichannel chios work 
# much faster:

    bindings {
        0 0   # from 0 => to 0
        1 1   # from 1 => to 1
    }
}
pcm.dsp0 {
    type plug
    slave.pcm "ossmix"     # use our new PCM here
}
# mixer0 like above
ctl.mixer0 {
    type hw
    card 0
}

but it still wont let me have two applications use the audio device at the same time, i know it will work if i set this up correctly tho, because i can have two instantes of alsaplayer going at the same time if i tell it to use the dmix plug. Do i have to enable a setting in the application itself to get it to work? should i use certain settings for my nforce2 ac97 onboard sound?

I tryed jack but i couldn't seemto get it to work either when ever i ran

jackd -d alsa

it says it couldn't open usr/lib/jack and says no drivers found.

[tsunam]

are you instructing the programs to use ossmix?

[-Bender-]

nope, how would i tell them to use ossmix?

[tsunam]

well for example mplayer you'd do -ao ossmix
in gaim you have the audio option in preferences/options and you can change it there. Its just a per program change so.

I also have noticed one thing missing from mine (forgot to copy it, Whoops ) and from yours.

pcm.!default {
type plug
slave.pcm "dmixer"
}

is the addition.

Also of some help is to tell oss devices to use alsa by default.
What should be in your /etc folder is a libao.conf file. In that you want to add default_driver=alsa

those two additions should allow you to have mixing without doing the above -ao shenanigans.

[-Bender-]

Thanks i got it to work i just had to change

pcm.!default {
type plug
slave.pcm "dmixer"
}

to use dmix instead of dmixer

pcm.!default {
type plug
slave.pcm "dmix"
}

Thanks for all your help

[tsunam]

glad it works for you, now enjoy your multiple channel software mixing . And you just learned something valuable as well.