System: IBM ThinkPad X30 on Ubuntu 6.06 LTS (Dapper Drake)

Problem: call to echo123 gave "problem with sound device". Running skype from a terminal window yielded the following error message:

CODE

$ skype
ALSA lib pcm_dmix.c:762:(snd_pcm_dmix_open) The dmix plugin supports only playback stream

Solution: per instructions in Linux Sound FAQ - Alsa, added the following lines to ~/.asoundrc

CODE

pcm.asymed {
        type asym
        playback.pcm "dmix"
        capture.pcm "dsnoop"
}

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

Results: two test calls to echo123 worked perfectly.

This is awesome info and I'm looking forward to implementing it as I have the exact same problem when using ALSA:

CODE

$ skype
ALSA lib pcm_dmix.c:803:(snd_pcm_dmix_open) The dmix plugin supports only playback stream

Can you please post your complete ~/.asoundrc to compare it with mine as I don't have dsnoop setup, for example, and there may be other differences as well. Thanks.

I was able to find the requested info in the asym page of the ALSA wiki. Following is my ~/.asoundrc for the Shuttle SN25P onboard sound card:

CODE

########################################################
#Full Duplex Software Mixing and Recording.

pcm.dmixed  {
    type dmix
    ipc_key 1024
    slave {
        pcm "hw:0,0"
        format S32_LE
        period_time 0
        period_size 1024
        buffer_size 16384
        rate 48000
    }
    bindings {
        0 0
        1 1
    }
}

pcm.dsnooped {
    ipc_key 1027
    type dsnoop
    slave.pcm "hw:0,0"
}

pcm.asymed {
        type asym
        playback.pcm "dmixed"
        capture.pcm "dsnooped"
}

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

ctl.!default {
    type hw
    card 0
    device 0
}

########################################################
#For aoss.

pcm.dsp0 {
    type plug
    slave.pcm "asymed"
}

ctl.mixer0 {
    type hw
    card 0
    device 0  
}

########################################################
#This is the normal spdif output profile (optical, toslink).

pcm.!spdif {
    type plug
    slave.pcm "hw:0,1"
}

Now I can use Skype and Amarok at the same time while hearing sounds from Thunderbird and Gaim.

This post has been edited by movrev: Sun Mar 18 2007, 22:04

Pardon my ignorance but are there any card specific lines in this snippet? Meaning, in order for this fix to work with my soundcard do I need to make changes?

I was able to find the requested info in the asym page of the ALSA wiki. Following is my ~/.asoundrc for the Shuttle SN25P onboard sound card:

CODE

########################################################
#Full Duplex Software Mixing and Recording.

pcm.dmixed  {
    type dmix
    ipc_key 1024
    slave {
        pcm "hw:0,0"
        format S32_LE
        period_time 0
        period_size 1024
        buffer_size 16384
        rate 48000
    }
    bindings {
        0 0
        1 1
    }
}

pcm.dsnooped {
    ipc_key 1027
    type dsnoop
    slave.pcm "hw:0,0"
}

pcm.asymed {
        type asym
        playback.pcm "dmixed"
        capture.pcm "dsnooped"
}

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

ctl.!default {
    type hw
    card 0
    device 0
}

########################################################
#For aoss.

pcm.dsp0 {
    type plug
    slave.pcm "asymed"
}

ctl.mixer0 {
    type hw
    card 0
    device 0  
}

########################################################
#This is the normal spdif output profile (optical, toslink).

pcm.!spdif {
    type plug
    slave.pcm "hw:0,1"
}

Now I can use Skype and Amarok at the same time while hearing sounds from Thunderbird and Gaim.

Pardon my ignorance but are there any card specific lines in this snippet? Meaning, in order for this fix to work with my soundcard do I need to make changes?

I don't know, but I copied the files verbatim and now it appears my skype setup finally works -- with software mixing and all Thanks for posting your solution Mikko!