duplicate to loopback route+multi .asoundrc

defaults.pcm.dmix.!rate 48000
defaults.pcm.dmix.!format S16_LE
pcm.multi {
    type multi
    slaves.a.pcm "dmix:RealCardName"
    slaves.a.channels 2
    slaves.b.pcm "dmix:Loopback"
    slaves.b.channels 2
    bindings.0 { slave a; channel 0; }
    bindings.1 { slave a; channel 1; }
    bindings.2 { slave b; channel 0; }
    bindings.3 { slave b; channel 1; }
}
pcm.both {
    type route
    slave.pcm "multi"
    ttable.0.0 1
    ttable.1.1 1
    ttable.0.2 1
    ttable.1.3 1
}
pcm.!default {
    type asym
    playback.pcm "plug:both"
    capture.pcm "plug:dsnoop:RealCardName"
}